GRIN

v. smile broadly; bare the teeth, grimace

n. broad smile; grimace, baring of the teeth

Grin may refer to:A facial expression: see SmileAlexander Grin, (1880 - 1932) a Russian novelistGRIN (novel), a novel by Hungarian writer Béla KasztovszkyGrin (album), an album by the thrash metal band CoronerGrin (band), a band formed by Nils LofgrenGrin (Grin album), an album by the above bandGRIN may refer to:GRIN (company), a video game developer based in SwedenGRIN, an acronym for gradient index: see Gradient index opticsGreat Images in NASA, a NASA-maintained collection of high-resolution aerospace related imagesGrand Rapids Information Network, a public television channelGermplasm Resources Information Network, a software project
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Noun
1. a facial expression characterized by turning up the corners of the mouth; usually shows pleasure or amusement
(synonym) smile, smiling, grinning
(hypernym) facial expression, facial gesture
(hyponym) smirk
Verb
1. to draw back the lips and reveal the teeth, in a smile, grimace, or snarl
(hypernym) smile
(derivation) grinner

n. gray, grey, grizzle

(v. t.)
To express by grinning.
  

(v. i.)
To show the teeth, as a dog; to snarl.
  

(v. i.)
To set the teeth together and open the lips, or to open the mouth and withdraw the lips from the teeth, so as to show them, as in laughter, scorn, or pain.
  

(n.)
The act of closing the teeth and showing them, or of withdrawing the lips and showing the teeth; a hard, forced, or sneering smile.
  

(n.)
A snare; a gin.