| Object Anchors |
| Object Wrapping |
| Objects |
| Objects - Linking |
| Odd and Even Pages |
| Odd Page Break |
| Odd Pages |
| Odt File Format |
| Office Add-ins - C# |
| Office Add-ins - JavaScript |
| Office Add-ins - TypeScript |
| Office Add-ins - VBA |
| Office Add-ins - VSTO |
| Office Assistant |
| Office Assistant - Animation |
| Office Backstage |
| Office Button |
| Office Clipboard |
| Office Diagostics |
| Office Document Cache |
| Office File Converter (OFC) |
| Office Logo - Office Assistant |
| Office Migration Planning Manager (OMPM) |
| Office Trusted Location |
| Office Versions |
| Office Word 2007 |
| Office.JS* |
| OfficeArt |
| Offline - Editing Documents |
| OLE (Object Linking and Embedding) |
| OLE Objects |
| OMath |
| OMPM (Office Migration Planning Manager) |
| One Page View |
| OneDrive |
| OneDrive for Business |
| Online Collaboration |
| Online Layout View |
| Online Meetings |
| Online Pictures |
| Online Resources |
| Online Video |
| Online View |
| Open Dialog Box |
| Open Document 120% |
| Open Documents in Print Layout View |
| Open in Browser |
| Open in Desktop App |
| Open XML File Format |
| OpenDocument Text Format (.odt) |
| Opening Documents |
| Opening Documents - No Updating |
| OpenType Font Options |
| Optimise - Minimum Size |
| Optimise - Standard |
| Optimising Before Saving |
| Option Button Control |
| Optional Hyphens |
| Options |
| Options - Compress Pictures |
| Options - General Options |
| Options - Save Options |
| Options - Tools |
| Options - Web Options |
| Order Toolbar |
| Ordinals |
| Organisation Chart - Add-in |
| Organisation Charts |
| Organisation Toolbar |
| Organiser - AutoText |
| Organiser - Macros |
| Organiser - Styles |
| Organiser - Toolbars |
| Organising Styles |
| Organizer Dialog Box |
| Orientation - Landscape |
| Orientation - Page |
| Orientation - Portrait |
| Original Showing Markup |
| Orphans |
| Outdents |
| Outline Bullets |
| Outline Format |
| Outline Level |
| Outline Numbered List |
| Outline Numbering |
| Outline of Document Content |
| Outline Style |
| Outline Text |
| Outline View |
| Outlines |
| Outlining - Lock Document |
| Outlining Toolbar |
| Outlook Attachments |
| Outlook Integration |
| Outlook Online Resource |
| Outlook Read Mail |
| Outlook Resource |
| Outlook Send Mail |
| Ovals |
| Overflowing Blocks of Text |
| Overline |
| Overtype Mode |
| OVR - Status Bar |