When you grin, you smile. You're likely to grin when your sister tells you a particularly funny knock-knock joke.

There's some disagreement about the difference between a grin and a smile — some define a grin as a broad smile that exposes your teeth, but others consider a grin to be a smile with lips tightly closed. Either way, a grin usually expresses amusement, although it sometimes has a mischievous or sly implication: "No one confessed to letting the rabbit loose in the classroom, but one student's grin gave her away."

Definitions of grin
  1. verb
    to draw back the lips and reveal the teeth, in a smile, grimace, or snarl
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    type of:
    change one's facial expression by spreading the lips, often to signal pleasure
  2. noun
    a facial expression characterized by turning up the corners of the mouth; usually shows pleasure or amusement
    synonyms: grinning, smile, smiling
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    a silly self-conscious smile
    a smile expressing smugness or scorn instead of pleasure
    type of:
    facial expression, facial gesture
    a gesture executed with the facial muscles
Word Family

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