broodyoudaoicibaDictYouDict[brood 词源字典]
brood: [OE] Like breed, brood came from a prehistoric Germanic base *brōd-, whose ultimate source was Indo-European *bhrē- ‘burn, heat’ (its other English descendants include braise, breath, and probably brawn). The underlying notion of brood is thus not so much ‘reproduction’ as ‘incubation, the warmth that promotes hatching’. The verbal sense ‘worry’ developed in the 18th century.
=> braise, brawn, breath, breed[brood etymology, brood origin, 英语词源]
brood (n.)youdaoicibaDictYouDict
Old English brod "brood, fetus, hatchling," from Proto-Germanic *brod (cognates: Middle Dutch broet, Old High German bruot, German Brut "brood"), literally "that which is hatched by heat," from *bro- "to warm, heat," from PIE *bhre- "burn, heat, incubate," from root *bhreue- "to boil, bubble, effervesce, burn" (see brew (v.)).
brood (v.)youdaoicibaDictYouDict
"sit on eggs, hatch," mid-15c., from brood (n.). The figurative meaning ("to incubate in the mind") is first recorded 1570s, from notion of "nursing" one's anger, resentment, etc. Related: Brooded; brooding.