bosom: [OE] The immediate source of Old English bōsm was West Germanic *bösm-, which also produced German busen and Dutch boezem. It has been conjectured that it may come ultimately from Indo-European *bhāghús, which perhaps meant ‘arm’ (source of English bought and possibly bow, as in ‘ship’s bow’); the early occurrence of phrases like ‘in someone’s bosom’ meaning ‘clasped to someone’s chest, in someone’s arms’ may support this. => bough, bow[bosom etymology, bosom origin, 英语词源]