Emily Dickinson Lexicon

AL-LY', v.t. [Fr. allier; reciprocal verb, s'allier, to match or confederate; from ad and lier, to tie or unite. L. ligo.]

1. To unite, or form a relation, as between families by marriage, or between princes and states by treaty, league or confederacy.
2. To form a relation by similitude, resemblance or friendship. Note. This word is more generally used in the passive form, as, families are allied by blood; or reciprocally, as, princes ally themselves to powerful states.