A partner in a business context (as opposed to a partner in the sense of a personal relationship).

plural of ex-partner

Someone who was once a partner (any sense) but is not one any more.

(neologism) single (not involved in a romantic relationship)

plural of domestic partner

(tennis) A player with whom one practises playing rallies, though not as a coach.

plural of partner dance

A person with whom someone has had sex.

a nominal partner

(intransitive) To form a partnership; to decide to work together in a duo.