One who is united in a relationship with another
A husband or wife
He'd never had a partner in all his time alive.
At balls he danced if a partner was needed.
But he showed the magnanimity of his nature by at once admitting Verus as his partner, giving him the tribunician and proconsular powers, and the titles Caesar and Augustus.
Can I be your partner every night?
He had married on the 2nd of June 1886 Miss Frances Folsom, a daughter of a former law partner in Buffalo.