n.
Pronunciation: ' blak- ˌ hed
Function: noun
Date: circa 1837
1 : a small plug of sebum blocking the duct of a sebaceous gland especially on the face
2 : a destructive disease of turkeys and related birds caused by a protozoan ( Histomonas meleagridis ) that invades the intestinal ceca and liver
3 : a larval clam or mussel attached to the skin or gills of a freshwater fish