allied
al·lied
/əˈlaıd, ˈæˌlaıd/ adj
1 a : joined in a relationship in which people, groups, countries etc., agree to work together
allied nations = nations that are allied to/with each other
1 b Allied always used before a noun : of or relating to the nations that fought together against Germany in World War I and World War II
Allied soldiers/troops/forces
2 somewhat formal : related or connected
chemistry and allied subjects
two families allied [=(more commonly) joined] by marriage
