Smile is an expression of happiness made by turning your mouth up at the corners.(noun)
An example of smile is the expression on your face when you are happy.
To smile is to make an expression of happiness on your face by turning up the corners of your mouth.(verb)
An example of smile is what you do when someone takes your picture.
See smile in Webster's New World College Dictionary
Origin: ME smilen, akin to Norw smile, Swed smila, prob. via MLowG *smilen < IE base *(s)mei-, to smile, be astonished > L mirus, wonderful, OE smearcian, to smile
See smile in American Heritage Dictionary 4
Origin: From Middle English smilen, to smile
Origin: , probably of Scandinavian origin; see smei- in Indo-European roots.
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