Dominus

·noun Master; sir;

— a title of respect formerly applied to a knight or a clergyman, and sometimes to the lord of a manor.

dominus
dŏmĭnus (in inscrr. sometimes written by syncop. DOMNVS), i, m. [Sanscr. damanas, he who subdues, ...

A New Latin Dictionary by Charlton T. Lewis Ph.D. and Charles Short, LL. D.
dominus
dominus ī, m 2 DOM-, a master, possessor, ruler, lord, proprietor, owner : aedium, T.: servos, Quo...

An Elementary Latin Dictionary