ラテン語のservire「仕える、奉仕する」から、servus「奴隷、召使い」から、おそらくは*ser「結合する、整える」から、語源はシリーズ、シリアルと同じ。
He no schuld neuer wondSense of "be useful, be beneficial, be suitable for a purpose or function" is from early 14c.; that of "take the place or meet the needs of, be equal to the task" is from late 14c.; that of "suffice" is from mid-15c. Meaning "render active military service" is from 1510s. Sporting sense, in tennis, badminton, etc., first recorded 1580s. Legal sense "present" (a writ, warrant,etc.), "give legal notice of" is from early 15c.
To seruen him fro fot to hond
["Amis and Amiloun," c. 1330]