Main Entry: hap·ten

Pronunciation: \ˈhap-ˌten\

Function: noun

Etymology: German, from Greek haptein to fasten

Date: 1921

: a small separable part of an antigen that reacts specifically with an antibody but is incapable of stimulating antibody production except in combination with a carrier protein molecule

— hap·ten·ic \hap-ˈte-nik\ adjective