concave
adj.
early 15c., from Old French concave (14c.) or directly from Latin concavus "hollow, arched, vaulted, curved," from com-, intensive prefix (see com-), + cavus "hollow" (see cave, n.).
〔李〕[con-;cav;-e] n.凹面 a.凹的 ←cav (L cavus)=hollow 凹陷
〔李〕[con-;cav;-e] n.凹面 a.凹的 ←cav (L cavus)=hollow 凹陷