Smart is the act of having intelligence.(noun)
An example of smart is someone with a high IQ.
Smart is sharp mental or physical pain.(noun)
An example of smart is how your arm feels after a shot.
The definition of smart is someone who is intelligent, someone who is well dressed and looking sharp or something that can act on its own accord.(adjective)
See smart in Webster's New World College Dictionary
Origin: ME smerten < OE smeortan, akin to Ger schmerzen < IE *mer-d < base *mer-, to rub away, fret > L mordere, to bite, sting, Gr smerdnos, frightful
Origin: ME smerte < base of v.
Origin: ME smerte < OE smeart < base of v.
See smart in American Heritage Dictionary 4
adjective smart·er, smart·est
Origin: Middle English, stinging, keen, alert
Origin: , from Old English smeart, causing pain.
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