smart

Etymology 1

From Middle English smerten, from Old English smeortan (“to smart”), from Proto-Germanic *smertaną (“to hurt, ache”), from Proto-Indo-European *(s)merd- (“to bite, sting”). Cognate with Scots smert, Dutch smarten, German schmerzen, Danish smerte, Swedish smärta.

verb

1. (intransitive) To hurt or sting.
   After being hit with a pitch, the batter exclaimed "Ouch, my arm smarts!"
2. (transitive) To cause a smart or sting in.
   A goad that […] smarts the flesh. a. 1652, Thomas Adams, Faith's Encouragement
3. (intransitive) To feel a pungent pain of mind; to feel sharp pain or grief; be punished severely; to feel the sting of evil.
   Meanwhile the Abate exulted in successful vengeance, and the marquis smarted beneath the stings of disappointment. 1790, Ann Ward Radcliffe, chapter 11, in A Sicilian Romance, HTML edition

Etymology 2

From Middle English smert, smart, from Old English smeart (“smarting, smart, painful”), from Proto-Germanic *smartaz (“hurting, aching”), from Proto-Indo-European *(s)merd- (“to bite, sting”). Cognate with Scots smert (“painful, smart”), Old Frisian smert (“sharp, painful”).

adj

1. Exhibiting social ability or cleverness.
2. (informal) Exhibiting intellectual knowledge, such as that found in books.
3. (often in combination) Equipped with intelligent behaviour (digital/computer technology).
   smart car
   smartcard
   smartphone
4. (technology, of human users) Able to see through a false positive of a digital / computer technology equipped with intelligent behavior.
   Sometimes, you are smarter than Microsoft Word's grammar checker, which occasionally flags legitimate sentences as being incorrect.
5. Good-looking; well dressed; fine; fashionable.
   a smart outfit
   You look smart in that business suit.
6. Cleverly shrewd and humorous in a way that may be rude and disrespectful.
   He became tired of his daughter's sarcasm and smart remarks.
   Don't get smart with me!
   Who, for the poor renown of being smart / Would leave a sting within a brother's heart? 1728, Edward Young, Satire
7. Sudden and intense.
   There is a smart shower at 5 P.M., and in the midst of it a hummingbird is busy about the flowers in the garden, unmindful of it, though you would think that each big drop that struck him would be a serious accident. 1860 July 9, Henry David Thoreau, journal entry, from Thoreau's bird-lore, Francis H. Allen (editor), Houghton Mifflin (Boston, 1910), Thoreau on Birds: notes on New England birds from the Journals of Henry David Thoreau, Beacon Press, (Boston, 1993), page 239
8. Causing sharp pain; stinging.
9. Sharp; keen; poignant.
   a smart pain
10. (Southern US, dated) Intense in feeling; painful. Used usually with the adverb intensifier right.
    He raised his voice, and it hurt her feelings right smart.
    That cast on his leg chaffs him right smart.
11. (archaic) Efficient; vigorous; brilliant.
12. (archaic) Pretentious; showy; spruce.
    a smart gown
13. (archaic) Brisk; fresh.
    a smart breeze

Etymology 3

From Middle English smerte, from smerten (“to smart”); see above. Cognate with Scots smert, Dutch smart, Low German smart, German Schmerz, Danish smerte, Swedish smärta. More above.

noun

1. A sharp, quick, lively pain; a sting.
   The smart of his wounded hand woke Scobie at two in the morning. 1948, Graham Greene, chapter 1, in The Heart of the Matter, London: Heinemann, Book One, Part One, section 8, page 42
2. Mental pain or suffering; grief; affliction.
3. Smart-money.
4. (slang, dated) A dandy; one who is smart in dress; one who is brisk, vivacious, or clever.