- an allying or being allied; specif., a union or joining, as of families by marriage
- a close association for a common objective, as of nations, political parties, etc.
- the agreement made for such an association
- the countries, groups, etc. forming such a connection
- similarity or relationship in characteristics, structure, etc.; affinity
Origin of allianceMiddle English aliaunce from Old French aleiance from alier: see ally