— bigheaded , adj. — bigheadedness , n.
/big"hed", -hed'/ , n.
1. Informal. an excessive estimate of one's importance; conceit.
2. Vet. Pathol.
a. an inflammatory swelling of the tissues of the head of sheep, caused by the anaerobic bacillus Clostridium novyi.
b. enlargement of the head and jawbones of horses resulting from nutritional hyperthyroidism.
[ 1795-1805, Amer.; BIG 1 + HEAD ]