alliance

(noun) the state of being allied or confederated. Synonyms: confederation.

(noun) a connection based on kinship or marriage or common interest. Synonyms: bond. Examples: "The shifting alliances within a large family." "Their friendship constitutes a powerful bond between them."

(noun) an organization of people (or countries) involved in a pact or treaty. Synonyms: coalition, alignment, alinement.

(noun) a formal agreement establishing an association or alliance between nations or other groups to achieve a particular aim.

(noun) the act of forming an alliance or confederation. Synonyms: confederation.