Definify.com
Webster 1913 Edition
Chin
Chin
(chĭn)
, Noun.
 [AS. 
cin
, akin to OS. kin
, G kinn
, Icel. kinn
, cheek, Dan. & Sw. kind
, L. gena
, Gr. [GREEK]; cf. Skr. hanu
. √232.] 1. 
The lower extremity of the face below the mouth; the point of the under jaw. 
2. 
(Zool.) 
The exterior or under surface embraced between the branches of the lower jaw bone, in birds. 
Webster 1828 Edition
Chin
CHIN
,Noun.