joined by treaty, agreement, or common cause

allied nations.

related; kindred

allied species.

( initial capital letter ) of or pertaining to the Allies.

adjective

disunited , estranged , unfriendly

adjective

affiliated , agnate , akin , amalgamated , associated , bound , cognate , combined , confederate , connate , connected , incident , in league , joined , joint , kindred , linked , married , related , unified , wed , connatural , consanguine , consanguineous , alike , similar , united