partner

(noun) a person's partner in marriage. Synonyms: spouse, married person, mate, better half.

(noun) an associate in an activity or endeavor or sphere of common interest. Synonyms: collaborator, cooperator, pardner. Examples: "The musician and the librettist were collaborators." "Sexual partners."

(noun) a person who is a member of a partnership.

(verb) provide with a partner.

(verb) act as a partner. Example: "Astaire partnered rogers."