It's clear the company hasn't given this icon more than a few ... Microsoft 365 Copilot is Office, which consists of Word, PowerPoint, Excel, OneNote, Outlook, and many others.

Excel, Publisher, PowerPoint, Access, Outlook, OneDrive and Skype for Business. Click on Webmail in the email channel. At the top right of the page (next to your name), go to the gear icon (settings) ...

Microsoft 365 may get all the attention, but the classic Microsoft Office suite also gets useful additions in every release.