On Android 5.0+, there is an option for multiple Users & Profiles, which is under
Settings > Users and is titled
Users & profiles. It is initially populated with a
Guest User as well as the
Owner User. To refer to non-owner Users & Profiles I would use and recognize
Secondary User/Profile (unless specifically asking about the
Guest User, which I would call
User accounts provide full access to Apps & Services.
Android 5.0+ Tablets (this feature does not appear to be on Phones) allow for User Profiles, such as the
Restricted User Profile, which can be set up to restrict what Apps and Services can be used by this user.
Accounts is a separate setting within Android's Settings. Each User Profile can have any number of Accounts set up (Emails, Pushbullet, etc.). These accounts are unique to each User.