IPA: //ˈteɪlˌkoʊt//
KK: /ˈteɪlˌkoʊt/
A formal coat for men that has a short front and long back, often worn for special occasions.
He wore a tailcoat to the wedding, looking very elegant.
Tailcoat → It is formed from "tail" (from Old French *tail*, meaning cut or to cut) and "coat" (from Old French *cote*, meaning a garment). The word "tailcoat" refers to a coat that is cut or styled in a specific way, typically with the back portion cut away to form tails.
Think of a coat that is 'cut' ('tail') in a special way, which is why a tailcoat has that distinctive style.