diff --git a/app/services/slash_commands/interpret_service.rb b/app/services/slash_commands/interpret_service.rb
index dc4a892b8b1..0d7838055fe 100644
--- a/app/services/slash_commands/interpret_service.rb
+++ b/app/services/slash_commands/interpret_service.rb
@@ -54,7 +54,7 @@ module SlashCommands
         issuable.closed? &&
         current_user.can?(:"update_#{issuable.to_ability_name}", issuable)
     end
-    command :reopen, :open do
+    command :reopen do
       @updates[:state_event] = 'reopen'
     end
 
@@ -86,7 +86,7 @@ module SlashCommands
         issuable.assignee_id? &&
         current_user.can?(:"admin_#{issuable.to_ability_name}", project)
     end
-    command :unassign, :remove_assignee do
+    command :unassign do
       @updates[:assignee_id] = nil
     end
 
@@ -109,7 +109,7 @@ module SlashCommands
         issuable.milestone_id? &&
         current_user.can?(:"admin_#{issuable.to_ability_name}", project)
     end
-    command :clear_milestone, :remove_milestone do
+    command :remove_milestone do
       @updates[:milestone_id] = nil
     end
 
@@ -119,33 +119,40 @@ module SlashCommands
       current_user.can?(:"admin_#{issuable.to_ability_name}", project) &&
         project.labels.any?
     end
-    command :label, :labels do |labels_param|
+    command :label do |labels_param|
       label_ids = find_label_ids(labels_param)
 
       @updates[:add_label_ids] = label_ids unless label_ids.empty?
     end
 
-    desc 'Remove label(s)'
+    desc 'Remove all or specific label(s)'
     params '~label1 ~"label 2"'
     condition do
       issuable.persisted? &&
         issuable.labels.any? &&
         current_user.can?(:"admin_#{issuable.to_ability_name}", project)
     end
-    command :unlabel, :remove_label, :remove_labels do |labels_param|
-      label_ids = find_label_ids(labels_param)
+    command :unlabel do |labels_param = nil|
+      if labels_param.present?
+        label_ids = find_label_ids(labels_param)
 
-      @updates[:remove_label_ids] = label_ids unless label_ids.empty?
+        @updates[:remove_label_ids] = label_ids unless label_ids.empty?
+      else
+        @updates[:label_ids] = []
+      end
     end
 
-    desc 'Remove all labels'
+    desc 'Replace all label(s)'
+    params '~label1 ~"label 2"'
     condition do
       issuable.persisted? &&
         issuable.labels.any? &&
         current_user.can?(:"admin_#{issuable.to_ability_name}", project)
     end
-    command :clear_labels, :clear_label do
-      @updates[:label_ids] = []
+    command :relabel do |labels_param|
+      label_ids = find_label_ids(labels_param)
+
+      @updates[:label_ids] = label_ids unless label_ids.empty?
     end
 
     desc 'Add a todo'
@@ -185,12 +192,12 @@ module SlashCommands
     end
 
     desc 'Set due date'
-    params '<in 2 days; this Friday; December 31st>'
+    params '<in 2 days | this Friday | December 31st>'
     condition do
       issuable.respond_to?(:due_date) &&
         current_user.can?(:"update_#{issuable.to_ability_name}", issuable)
     end
-    command :due, :due_date do |due_date_param|
+    command :due do |due_date_param|
       due_date = Chronic.parse(due_date_param).try(:to_date)
 
       @updates[:due_date] = due_date if due_date
@@ -203,7 +210,7 @@ module SlashCommands
         issuable.due_date? &&
         current_user.can?(:"update_#{issuable.to_ability_name}", issuable)
     end
-    command :clear_due_date do
+    command :remove_due_date do
       @updates[:due_date] = nil
     end
 
diff --git a/doc/workflow/slash_commands.md b/doc/workflow/slash_commands.md
index 75fec7bcdb9..91d69d4e77e 100644
--- a/doc/workflow/slash_commands.md
+++ b/doc/workflow/slash_commands.md
@@ -5,26 +5,26 @@ requests that are usually done by clicking buttons or dropdowns in GitLab's UI.
 You can enter these commands while creating a new issue or merge request, and
 in comments. Each command should be on a separate line in order to be properly
 detected and executed. The commands are removed from the issue, merge request or
-comment body before it is saved and will not be visible as such to anyone else.
+comment body before it is saved and will not be visible to anyone else.
 
-Here is a list of all of the available commands and descriptions about what they
+Below is a list of all of the available commands and descriptions about what they
 do.
 
-| Command                    | Aliases             | Action       |
-|:---------------------------|:--------------------|:-------------|
-| `/close`                   | None                | Close the issue or merge request |
-| `/reopen`                  | `/open`             | Reopen the issue or merge request |
-| `/title <New title>`       | None                | Change title |
-| `/assign @username`        | None                | Assign |
-| `/unassign`                | `/remove_assignee`  | Remove assignee |
-| `/milestone %milestone`    | None                | Set milestone |
-| `/clear_milestone`         | `/remove_milestone` | Remove milestone |
-| `/label ~foo ~"bar baz"`   | `/labels`           | Add label(s) |
-| `/unlabel ~foo ~"bar baz"` | `/remove_label`, `remove_labels` | Remove label(s) |
-| `/clear_labels`            | `/clear_label`      | Clear all labels |
-| `/todo`                    | None                | Add a todo |
-| `/done`                    | None                | Mark todo as done |
-| `/subscribe`               | None                | Subscribe |
-| `/unsubscribe`             | None                | Unsubscribe |
-| `/due <in 2 days; this Friday; December 31st>` | `/due_date` | Set due date |
-| `/clear_due_date`          | None                | Remove due date |
+| Command                    | Action       |
+|:---------------------------|:-------------|
+| `/close`                   | Close the issue or merge request |
+| `/reopen`                  | Reopen the issue or merge request |
+| `/title <New title>`       | Change title |
+| `/assign @username`        | Assign |
+| `/unassign`                | Remove assignee |
+| `/milestone %milestone`    | Set milestone |
+| `/remove_milestone`        | Remove milestone |
+| `/label ~foo ~"bar baz"`   | Add label(s) |
+| `/unlabel ~foo ~"bar baz"` | Remove all or specific label(s) |
+| `/relabel ~foo ~"bar baz"` | Replace all label(s) |
+| `/todo`                    | Add a todo |
+| `/done`                    | Mark todo as done |
+| `/subscribe`               | Subscribe |
+| `/unsubscribe`             | Unsubscribe |
+| `/due <in 2 days | this Friday | December 31st>` | Set due date |
+| `/remove_due_date`          | Remove due date |
diff --git a/spec/features/issues/user_uses_slash_commands_spec.rb b/spec/features/issues/user_uses_slash_commands_spec.rb
index 510f4254b54..2883e392694 100644
--- a/spec/features/issues/user_uses_slash_commands_spec.rb
+++ b/spec/features/issues/user_uses_slash_commands_spec.rb
@@ -22,11 +22,11 @@ feature 'Issues > User uses slash commands', feature: true, js: true do
 
       it 'does not create a note, and sets the due date accordingly' do
         page.within('.js-main-target-form') do
-          fill_in 'note[note]', with: "/due_date 2016-08-28"
+          fill_in 'note[note]', with: "/due 2016-08-28"
           click_button 'Comment'
         end
 
-        expect(page).not_to have_content '/due_date 2016-08-28'
+        expect(page).not_to have_content '/due 2016-08-28'
         expect(page).to have_content 'Your commands have been executed!'
 
         issue.reload
@@ -42,11 +42,11 @@ feature 'Issues > User uses slash commands', feature: true, js: true do
         expect(issue.due_date).to eq Date.new(2016, 8, 28)
 
         page.within('.js-main-target-form') do
-          fill_in 'note[note]', with: "/clear_due_date"
+          fill_in 'note[note]', with: "/remove_due_date"
           click_button 'Comment'
         end
 
-        expect(page).not_to have_content '/clear_due_date'
+        expect(page).not_to have_content '/remove_due_date'
         expect(page).to have_content 'Your commands have been executed!'
 
         issue.reload
diff --git a/spec/features/merge_requests/user_uses_slash_commands_spec.rb b/spec/features/merge_requests/user_uses_slash_commands_spec.rb
index 08c452c6e59..d9ef0d18074 100644
--- a/spec/features/merge_requests/user_uses_slash_commands_spec.rb
+++ b/spec/features/merge_requests/user_uses_slash_commands_spec.rb
@@ -22,11 +22,11 @@ feature 'Merge Requests > User uses slash commands', feature: true, js: true do
 
     it 'does not recognize the command nor create a note' do
       page.within('.js-main-target-form') do
-        fill_in 'note[note]', with: "/due_date 2016-08-28"
+        fill_in 'note[note]', with: "/due 2016-08-28"
         click_button 'Comment'
       end
 
-      expect(page).not_to have_content '/due_date 2016-08-28'
+      expect(page).not_to have_content '/due 2016-08-28'
     end
   end
 end
diff --git a/spec/lib/gitlab/slash_commands/extractor_spec.rb b/spec/lib/gitlab/slash_commands/extractor_spec.rb
index 09f909dcdd2..1e4954c4af8 100644
--- a/spec/lib/gitlab/slash_commands/extractor_spec.rb
+++ b/spec/lib/gitlab/slash_commands/extractor_spec.rb
@@ -18,7 +18,7 @@ describe Gitlab::SlashCommands::Extractor do
     it 'extracts command' do
       msg, commands = extractor.extract_commands(original_msg)
 
-      expect(commands).to eq [['open']]
+      expect(commands).to eq [['reopen']]
       expect(msg).to eq final_msg
     end
   end
@@ -45,31 +45,31 @@ describe Gitlab::SlashCommands::Extractor do
     describe 'command with no argument' do
       context 'at the start of content' do
         it_behaves_like 'command with no argument' do
-          let(:original_msg) { "/open\nworld" }
+          let(:original_msg) { "/reopen\nworld" }
           let(:final_msg) { "world" }
         end
       end
 
       context 'in the middle of content' do
         it_behaves_like 'command with no argument' do
-          let(:original_msg) { "hello\n/open\nworld" }
+          let(:original_msg) { "hello\n/reopen\nworld" }
           let(:final_msg) { "hello\nworld" }
         end
       end
 
       context 'in the middle of a line' do
         it 'does not extract command' do
-          msg = "hello\nworld /open"
+          msg = "hello\nworld /reopen"
           msg, commands = extractor.extract_commands(msg)
 
           expect(commands).to be_empty
-          expect(msg).to eq "hello\nworld /open"
+          expect(msg).to eq "hello\nworld /reopen"
         end
       end
 
       context 'at the end of content' do
         it_behaves_like 'command with no argument' do
-          let(:original_msg) { "hello\n/open" }
+          let(:original_msg) { "hello\n/reopen" }
           let(:final_msg) { "hello" }
         end
       end
@@ -170,10 +170,10 @@ describe Gitlab::SlashCommands::Extractor do
     end
 
     it 'extracts multiple commands' do
-      msg = %(hello\n/power @user.name %9.10 ~"bar baz.2" label\nworld\n/open)
+      msg = %(hello\n/power @user.name %9.10 ~"bar baz.2" label\nworld\n/reopen)
       msg, commands = extractor.extract_commands(msg)
 
-      expect(commands).to eq [['power', '@user.name %9.10 ~"bar baz.2" label'], ['open']]
+      expect(commands).to eq [['power', '@user.name %9.10 ~"bar baz.2" label'], ['reopen']]
       expect(msg).to eq "hello\nworld"
     end
 
diff --git a/spec/services/notes/slash_commands_service_spec.rb b/spec/services/notes/slash_commands_service_spec.rb
index 9a262fcf32f..4f231aab161 100644
--- a/spec/services/notes/slash_commands_service_spec.rb
+++ b/spec/services/notes/slash_commands_service_spec.rb
@@ -69,12 +69,12 @@ describe Notes::SlashCommandsService, services: true do
         end
       end
 
-      describe '/open' do
+      describe '/reopen' do
         before do
           note.noteable.close!
           expect(note.noteable).to be_closed
         end
-        let(:note_text) { '/open' }
+        let(:note_text) { '/reopen' }
 
         it 'opens the noteable, and leave no note' do
           content, command_params = service.extract_commands(note)
@@ -104,12 +104,12 @@ describe Notes::SlashCommandsService, services: true do
         end
       end
 
-      describe '/open' do
+      describe '/reopen' do
         before do
           note.noteable.close
           expect(note.noteable).to be_closed
         end
-        let(:note_text) { "HELLO\n/open\nWORLD" }
+        let(:note_text) { "HELLO\n/reopen\nWORLD" }
 
         it 'opens the noteable' do
           content, command_params = service.extract_commands(note)
diff --git a/spec/services/slash_commands/interpret_service_spec.rb b/spec/services/slash_commands/interpret_service_spec.rb
index c20aa90ddde..a616275e883 100644
--- a/spec/services/slash_commands/interpret_service_spec.rb
+++ b/spec/services/slash_commands/interpret_service_spec.rb
@@ -16,8 +16,8 @@ describe SlashCommands::InterpretService, services: true do
     let(:service) { described_class.new(project, user) }
     let(:merge_request) { create(:merge_request, source_project: project) }
 
-    shared_examples 'open command' do
-      it 'returns state_event: "open" if content contains /open' do
+    shared_examples 'reopen command' do
+      it 'returns state_event: "reopen" if content contains /reopen' do
         issuable.close!
         _, updates = service.execute(content, issuable)
 
@@ -26,7 +26,7 @@ describe SlashCommands::InterpretService, services: true do
     end
 
     shared_examples 'close command' do
-      it 'returns state_event: "close" if content contains /open' do
+      it 'returns state_event: "close" if content contains /close' do
         _, updates = service.execute(content, issuable)
 
         expect(updates).to eq(state_event: 'close')
@@ -67,8 +67,8 @@ describe SlashCommands::InterpretService, services: true do
       end
     end
 
-    shared_examples 'clear_milestone command' do
-      it 'populates milestone_id: nil if content contains /clear_milestone' do
+    shared_examples 'remove_milestone command' do
+      it 'populates milestone_id: nil if content contains /remove_milestone' do
         issuable.update(milestone_id: milestone.id)
         _, updates = service.execute(content, issuable)
 
@@ -95,8 +95,8 @@ describe SlashCommands::InterpretService, services: true do
       end
     end
 
-    shared_examples 'clear_labels command' do
-      it 'populates label_ids: [] if content contains /clear_labels' do
+    shared_examples 'unlabel command with no argument' do
+      it 'populates label_ids: [] if content contains /unlabel with no arguments' do
         issuable.update(label_ids: [inprogress.id]) # populate the label
         _, updates = service.execute(content, issuable)
 
@@ -104,6 +104,16 @@ describe SlashCommands::InterpretService, services: true do
       end
     end
 
+    shared_examples 'relabel command' do
+      it 'populates label_ids: [] if content contains /relabel' do
+        issuable.update(label_ids: [bug.id]) # populate the label
+        inprogress # populate the label
+        _, updates = service.execute(content, issuable)
+
+        expect(updates).to eq(label_ids: [inprogress.id])
+      end
+    end
+
     shared_examples 'todo command' do
       it 'populates todo_event: "add" if content contains /todo' do
         _, updates = service.execute(content, issuable)
@@ -138,16 +148,16 @@ describe SlashCommands::InterpretService, services: true do
       end
     end
 
-    shared_examples 'due_date command' do
-      it 'populates due_date: Date.new(2016, 8, 28) if content contains /due_date 2016-08-28' do
+    shared_examples 'due command' do
+      it 'populates due_date: Date.new(2016, 8, 28) if content contains /due 2016-08-28' do
         _, updates = service.execute(content, issuable)
 
         expect(updates).to eq(due_date: defined?(expected_date) ? expected_date : Date.new(2016, 8, 28))
       end
     end
 
-    shared_examples 'clear_due_date command' do
-      it 'populates due_date: nil if content contains /clear_due_date' do
+    shared_examples 'remove_due_date command' do
+      it 'populates due_date: nil if content contains /remove_due_date' do
         issuable.update(due_date: Date.today)
         _, updates = service.execute(content, issuable)
 
@@ -163,21 +173,16 @@ describe SlashCommands::InterpretService, services: true do
       end
     end
 
-    it_behaves_like 'open command' do
-      let(:content) { '/open' }
-      let(:issuable) { issue }
-    end
-
-    it_behaves_like 'open command' do
-      let(:content) { '/open' }
-      let(:issuable) { merge_request }
-    end
-
-    it_behaves_like 'open command' do
+    it_behaves_like 'reopen command' do
       let(:content) { '/reopen' }
       let(:issuable) { issue }
     end
 
+    it_behaves_like 'reopen command' do
+      let(:content) { '/reopen' }
+      let(:issuable) { merge_request }
+    end
+
     it_behaves_like 'close command' do
       let(:content) { '/close' }
       let(:issuable) { issue }
@@ -233,11 +238,6 @@ describe SlashCommands::InterpretService, services: true do
       let(:issuable) { merge_request }
     end
 
-    it_behaves_like 'unassign command' do
-      let(:content) { '/remove_assignee' }
-      let(:issuable) { issue }
-    end
-
     it_behaves_like 'milestone command' do
       let(:content) { "/milestone %#{milestone.title}" }
       let(:issuable) { issue }
@@ -248,21 +248,16 @@ describe SlashCommands::InterpretService, services: true do
       let(:issuable) { merge_request }
     end
 
-    it_behaves_like 'clear_milestone command' do
-      let(:content) { '/clear_milestone' }
-      let(:issuable) { issue }
-    end
-
-    it_behaves_like 'clear_milestone command' do
-      let(:content) { '/clear_milestone' }
-      let(:issuable) { merge_request }
-    end
-
-    it_behaves_like 'clear_milestone command' do
+    it_behaves_like 'remove_milestone command' do
       let(:content) { '/remove_milestone' }
       let(:issuable) { issue }
     end
 
+    it_behaves_like 'remove_milestone command' do
+      let(:content) { '/remove_milestone' }
+      let(:issuable) { merge_request }
+    end
+
     it_behaves_like 'label command' do
       let(:content) { %(/label ~"#{inprogress.title}" ~#{bug.title} ~unknown) }
       let(:issuable) { issue }
@@ -273,11 +268,6 @@ describe SlashCommands::InterpretService, services: true do
       let(:issuable) { merge_request }
     end
 
-    it_behaves_like 'label command' do
-      let(:content) { %(/labels ~"#{inprogress.title}" ~#{bug.title} ~unknown) }
-      let(:issuable) { issue }
-    end
-
     it_behaves_like 'unlabel command' do
       let(:content) { %(/unlabel ~"#{inprogress.title}") }
       let(:issuable) { issue }
@@ -288,31 +278,26 @@ describe SlashCommands::InterpretService, services: true do
       let(:issuable) { merge_request }
     end
 
-    it_behaves_like 'unlabel command' do
-      let(:content) { %(/remove_labels ~"#{inprogress.title}") }
+    it_behaves_like 'unlabel command with no argument' do
+      let(:content) { %(/unlabel) }
       let(:issuable) { issue }
     end
 
-    it_behaves_like 'unlabel command' do
-      let(:content) { %(/remove_label ~"#{inprogress.title}") }
-      let(:issuable) { issue }
-    end
-
-    it_behaves_like 'clear_labels command' do
-      let(:content) { '/clear_labels' }
-      let(:issuable) { issue }
-    end
-
-    it_behaves_like 'clear_labels command' do
-      let(:content) { '/clear_labels' }
+    it_behaves_like 'unlabel command with no argument' do
+      let(:content) { %(/unlabel) }
       let(:issuable) { merge_request }
     end
 
-    it_behaves_like 'clear_labels command' do
-      let(:content) { '/clear_label' }
+    it_behaves_like 'relabel command' do
+      let(:content) { %(/relabel ~"#{inprogress.title}") }
       let(:issuable) { issue }
     end
 
+    it_behaves_like 'relabel command' do
+      let(:content) { %(/relabel ~"#{inprogress.title}") }
+      let(:issuable) { merge_request }
+    end
+
     it_behaves_like 'todo command' do
       let(:content) { '/todo' }
       let(:issuable) { issue }
@@ -353,46 +338,46 @@ describe SlashCommands::InterpretService, services: true do
       let(:issuable) { merge_request }
     end
 
-    it_behaves_like 'due_date command' do
-      let(:content) { '/due_date 2016-08-28' }
+    it_behaves_like 'due command' do
+      let(:content) { '/due 2016-08-28' }
       let(:issuable) { issue }
     end
 
-    it_behaves_like 'due_date command' do
+    it_behaves_like 'due command' do
       let(:content) { '/due tomorrow' }
       let(:issuable) { issue }
       let(:expected_date) { Date.tomorrow }
     end
 
-    it_behaves_like 'due_date command' do
+    it_behaves_like 'due command' do
       let(:content) { '/due 5 days from now' }
       let(:issuable) { issue }
       let(:expected_date) { 5.days.from_now.to_date }
     end
 
-    it_behaves_like 'due_date command' do
+    it_behaves_like 'due command' do
       let(:content) { '/due in 2 days' }
       let(:issuable) { issue }
       let(:expected_date) { 2.days.from_now.to_date }
     end
 
     it_behaves_like 'empty command' do
-      let(:content) { '/due_date foo bar' }
+      let(:content) { '/due foo bar' }
       let(:issuable) { issue }
     end
 
     it_behaves_like 'empty command' do
-      let(:content) { '/due_date 2016-08-28' }
+      let(:content) { '/due 2016-08-28' }
       let(:issuable) { merge_request }
     end
 
-    it_behaves_like 'clear_due_date command' do
-      let(:content) { '/clear_due_date' }
+    it_behaves_like 'remove_due_date command' do
+      let(:content) { '/remove_due_date' }
       let(:issuable) { issue }
     end
 
     it_behaves_like 'empty command' do
-      let(:content) { '/clear_due_date' }
+      let(:content) { '/remove_due_date' }
       let(:issuable) { merge_request }
     end
   end
diff --git a/spec/support/issuable_create_service_slash_commands_shared_examples.rb b/spec/support/issuable_create_service_slash_commands_shared_examples.rb
index bd0201c866f..5f9645ed44f 100644
--- a/spec/support/issuable_create_service_slash_commands_shared_examples.rb
+++ b/spec/support/issuable_create_service_slash_commands_shared_examples.rb
@@ -14,7 +14,7 @@ shared_examples 'new issuable record that supports slash commands' do
   context 'with labels in command only' do
     let(:example_params) do
       {
-        description: "/label ~#{labels.first.name} ~#{labels.second.name}\n/remove_label ~#{labels.third.name}"
+        description: "/label ~#{labels.first.name} ~#{labels.second.name}\n/unlabel ~#{labels.third.name}"
       }
     end
 
@@ -28,7 +28,7 @@ shared_examples 'new issuable record that supports slash commands' do
     let(:example_params) do
       {
         label_ids: [labels.second.id],
-        description: "/label ~#{labels.first.name}\n/remove_label ~#{labels.third.name}"
+        description: "/label ~#{labels.first.name}\n/unlabel ~#{labels.third.name}"
       }
     end