Main Entry: el·lip·soid

Pronunciation: \i-ˈlip-ˌsȯid, e-\

Function: noun

Date: 1721

: a surface all plane sections of which are ellipses or circles

— el·lip·soi·dal \i-ˌlip-ˈsȯi-d^əl, (ˌ)e-\ also ellipsoid adjective