Synonyms of alliance in English:

alliance


See US English definition of alliance

See UK English definition of alliance

See Spanish definition of alianza

noun

1‘a defensive alliance between Australia and New Zealand’

SYNONYMS
association, union, league, treaty, pact, compact, entente, concordat
bloc, confederation, federation, confederacy, coalition, consortium, combine, syndicate, affiliation, partnership
fraternity, brotherhood, sorority, team, ring, society, club, guild, group, organization

2‘an alliance between medicine and morality’

SYNONYMS
relationship, affinity, association, connection, closeness, kinship, propinquity
ANTONYMS

distance, separation