Old English sculdor "shoulder," from West Germanic *skuldro (cf. Middle Dutch scouder, Dutch schouder, Old Frisian skoldere, Middle Low German scholder, Old High German scultra, German Schulter), of unknown origin, perhaps related to shield (n.). Meaning "edge of the road" is attested from 1933. Cold shoulder (Neh. ix:29) translates Latin humerum recedentum dare in Vulgate (but see cold shoulder). Shoulder-length, of hair, is from 1951.
c.1300, "to push with the shoulder," from shoulder (n.). Meaning "take a burden" first recorded 1580s. The military sense is from 1590s. Related: Shouldered; shouldering.
shoulder shoul·der (shōl'dər)
The joint connecting the arm with the torso.
The part of the human body between the neck and upper arm.
Honestly and directly; unflinchingly; straight: He gave it to us straight from the shoulder
[1856+; perhaps from the notion of an honest blow delivered straight from the shoulder rather than deviously, from the side, etc]