c.1600, "arrange, settle, compose," from O.Fr. ajoster "to join," from L.L. adjuxtare "to bring near," from L. ad- "to" + juxta "next," related to jungere "to join" (see jugular). Influenced by folk etymology derivation from L. justus "just, equitable, fair." Meaning "to get used to" first recorded 1924. Related: Adjustable; adjuster; adjustor (1895, of certain muscles; see -er).