n.
Variant: or chap · er · on
Pronunciation: ' sha-p ə - ˌ r ō n
Function: noun
Etymology: French chaperon, literally, hood, from Middle French, head covering, from chape
Date: 1720
1 : a person (as a matron) who for propriety accompanies one or more young unmarried women in public or in mixed company
2 : an older person who accompanies young people at a social gathering to ensure proper behavior broadly : one delegated to ensure proper behavior
3 : any of a class of proteins that facilitate the proper folding of proteins by binding to and stabilizing unfolded or partially folded proteins ― called also molecular chaperone