prime minister noun
ADJ. deputy | acting, caretaker, interim, transitional | incumbent, present | former, previous | outgoing | strong | beleaguered The beleaguered prime minister is coming under yet more pressure. | Conservative, Labour, etc.
VERB + PRIME MINISTER appoint, appoint sb (as), elect, elect sb (as) | serve as He served briefly as prime minister from 1920 to 1921. (For more verbs see the entry for minister.)
PREP. under a/the ~ She held office under two different prime ministers.