Main Entry: breast·plate

Pronunciation: \ˈbres(t)-ˌplāt\

Function: noun

Date: 14th century

1 : a usually metal plate worn as defensive armor for the breast — see armor illustration
2 : a vestment worn in ancient times by a Jewish high priest and set with 12 gems bearing the names of the tribes of Israel
3 : a piece against which a worker's breast is pressed in operating a tool (as a breast drill)