What are synonyms of companion?

Here are some synonyms for "companion," categorized for clarity:

General:

* Friend

* Associate

* Acquaintance

* Comrade

* Buddy

* Pal

* Partner

* Mate

* Fellow

* Chum

More formal:

* Associate

* Colleague

* Peer

* Confidante

* Aide

* Escort

* Attendant

Specific to a relationship:

* Spouse

* Partner (romantic)

* Roommate

* Housemate

* Cohabitant

For animals:

* Pet

* Animal companion

* Best friend (informal)

Other:

* Sidekick

* Travelling companion

* Guide

* Mentor

* Companion animal

The best synonym will depend on the specific context of your sentence.