generatrix

noun

gen·​er·​a·​trix ˌje-nə-ˈrā-triks 

plural generatrices ˌje-nə-ˈrā-trə-ˌsēz 

ˌje-nə-rə-ˈtrī-(ˌ)sēz

: a point, line, or surface whose motion generates a line, surface, or solid

Word History

First Known Use

1840, in the meaning defined above