Main Entry: neu·tri·no

Pronunciation: \nü-ˈtrē-(ˌ)nō, nyü-\

Function: noun

Inflected Form(s): plural neu·tri·nos

Etymology: Italian, from neutro neutral, neuter, from Latin neutr-, neuter

Date: 1934

: an uncharged elementary particle that is believed to have a very small mass, that has any of three forms, and that interacts only rarely with other particles

— neu·tri·no·less \-ləs\ adjective