sculdor

Sculdor in Old English is of uncertain deeper origin. It appears in all the Germanic languages — German Schulter, Dutch schouder, Old Norse skulldr — but has no clear cognates in Latin, Greek, Sanskrit, or any other branch of Indo-European. The word may derive from a Proto-Germanic root meaning 'shield,' referring to the shoulder blade's flat, protective shape. Or it may be related to a root meaning 'to push.' Certainty is absent.

The shoulder is the most mobile joint in the human body. It is a ball-and-socket joint — the head of the humerus (upper arm bone) fits into the glenoid cavity of the scapula (shoulder blade) — but unlike the hip (also a ball-and-socket joint), the shoulder sacrifices stability for range of motion. You can move your arm in nearly any direction. The trade-off is vulnerability: shoulder dislocations are far more common than hip dislocations.

The figurative meanings are enormous. Shouldering a burden. A shoulder to cry on. Cold shoulder. Shoulder to shoulder. Hard shoulder (the edge of a road). The shoulder is the body's weight-bearing metaphor — the place where responsibility sits. Atlas holds the sky on his shoulders. Parents carry children on their shoulders. The joint that lifts the arm became the joint that lifts everything else.

The shoulder pad — first used in American football in the 1890s and adopted by women's fashion in the 1940s and again in the 1980s — broadened the shoulder artificially. In both cases, wider shoulders signified power. The body part that carries weight was enlarged to suggest the capacity to carry more.