- adjoin (v.)
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- c. 1300, "unite, ally" from Old French ajoin- stem of ajoindre "join together, unite," from Latin adiungere "fasten on, harness, join to," from ad- "to" (see ad-) + iungere "to bind together" (see jugular). Meaning "be contiguous with, be adjacent to" is from late 14c. Related: Adjoined; adjoining.