Like most words, it can have different meanings in different contexts. Intimate can be a verb, a noun or an adjective.
Verb (transitive)- to tell someone something private or secret, or to hint at or imply something secret or private.
Noun - a very close friend
Adjective - private, personal, or sexual
Also in the phrasal verbs "be intimate" or "get intimate", it can describe engaging in sexual activity. They're usually collocated with the preposition "with."