affiliate

transitive verb

Officially attach or connect (a subsidiary group or a person) to an organization.

noun

A person or organization officially attached to a larger body.

SYNONYMS

align withally withamalgamate withassociate withband together withbe in league withcoalesce withcombine withconfederate withcooperate withfederate withform a confederation withform a federation withform an alliance withjoin forces withjoin up withjoin withmerge withteam up withunite with