adj.
Pronunciation: kän- ' k ā v, ' kän- ˌ
Function: adjective
Etymology: Middle English, from Latin concavus, from com- + cavus hollow ― more at CAVE
Date: 15th century
1 : hollowed or rounded inward like the inside of a bowl
2 : arched in : curving in ― used of the side of a curve or surface on which neighboring normals to the curve or surface converge and on which lies the chord joining two neighboring points of the curve or surface