WordNet sense 1 (a person who is frequently in the company of another):

companion, comrade, familiar, fellow

WordNet sense 2 (a degree granted by a two-year college on successful completion of the undergraduates course of studies):

associate degree

WordNet sense 3 (keep company with; hang out with):

affiliate, assort, consort, affiliate, consort

WordNet sense 4 (bring or come into association or action):

consociate, consociate

WordNet sense 5 (lower in rank or importance):

low-level, subordinate

WordNet sense 6 (make a logical or causal connection):

connect, link, relate, colligate, tie in