Ninchin
Description of a person who has a divoted chin. Name derived from the crossing of 'ninja foot' and 'chin'. See also "Grenade Chin".
Matty has a ninchin, you could hide a roll of dimes up in that bitch!
Ninchin
An individual with an under bite.
"That new girl with an under bite is a ninchin." Girl- "I'm not a ninchin!"