1. (n.) The young birds hatched at one time; a hatch; as, a brood of chickens.

2. (n.) The young from the same dam, whether produced at the same time or not; young children of the same mother, especially if nearly of the same age; offspring; progeny; as, a woman with a brood of children.

3. (v. t.) That which is bred or produced; breed; species.

4. (v. t.) Heavy waste in tin and copper ores.

5. (a.) Sitting or inclined to sit on eggs.

6. (a.) Kept for breeding from; as, a brood mare; brood stock; having young; as, a brood sow.

7. (v. i.) To sit on and cover eggs, as a fowl, for the purpose of warming them and hatching the young; or to sit over and cover young, as a hen her chickens, in order to warm and protect them; hence, to sit quietly, as if brooding.

8. (v. i.) To have the mind dwell continuously or moodily on a subject; to think long and anxiously; to be in a state of gloomy, serious thought; -- usually followed by over or on; as, to brood over misfortunes.

9. (v. t.) To sit over, cover, and cherish; as, a hen broods her chickens.

10. (v. t.) To cherish with care.

11. (v. t.) To think anxiously or moodily upon.