the.com/brood
To sit on eggs, or to sit on thoughts that never hatch.
means To dwell darkly on something, or to incubate eggs — and also the whole batch of offspring produced at once.
from From Old English brod, kin to the warmth of breeding; the gloomy human sense came later, when we noticed thinking too long resembles a hen who won't leave the nest.
Group nounA brood is birds hatched together, one clutch.
Verb pivotSame word: hatching eggs and hatching worries.
Brood XCicadas brood underground for seventeen patient years.