[n] persistent morbid meditation on a problem
[n] sitting on eggs so as to hatch them by the warmth of the body
[adj] persistently or morbidly thoughtful
[adj] good at incubating eggs especially a fowl kept for that purpose; "a brood hen"
brood, broody, contemplative, hatching, incubation, meditative, musing, oviparous, pensive, pensiveness, pondering, reflective, ruminative, thoughtful