ally noun

ADJ. great, important, powerful, strong | close Charles remained a close ally of the French king. | loyal, reliable, staunch, trusted | natural, useful, valuable | old, traditional Portugal is a traditional ally of England. | erstwhile, former | wartime | potential | European, NATO, Western, etc. | political

VERB + ALLY have Jane felt that she had an ally. | find, gain, get | lose

PREP. ~ against He now had an ally against his boss.

PHRASES find/have an ally in sb She had found an ally in her old teacher. | a friend and ally a friend and ally of the president