sly

Etymology

It is inherited from Middle English sleigh, also sleh, sli and sly,^[2][3][4][5] borrowed from Old Norse slœgr (“clever, cunning”).^{[6][7][8][9][10]} The OED notes that the northern form slee and the midland and southern sligh are the regular English outcomes.^[6] The Norse adjective is explained as originally meaning "able to strike", from slóg-, the preterite stem of slá (“to strike”),^{[6][8][10][11]} the Norse cognate of slay;^[8][5] Etymonline calls this derivation probable and traces it through Proto-Germanic *slōgiz to Proto-Indo-European *slak- (“to strike, hit”).^[12][13] Its cognates are Icelandic slægur and Norwegian sløg (“cunning, crafty”).^[6][4] Etymonline compares German verschlagen (“cunning, crafty”) and schlagfertig (“quick-witted”), from schlagen (“to strike”), though the exact relation is uncertain.^[12] Etymonline and Klein also relate Low German slū (“cunning, sly”), the source of Dutch sluw,^[12][5] while Skeat and Wiktionary keep that group apart.^[14][13] The noun sleight comes from an Old Norse derivative of the same adjective.^[15][6]

Earliest recorded meaning

Of people, skilful, clever, dexterous, expert or wise: about 1175, in the Ormulum.^[6] Etymonline also dates the word to the late 12th century, with the senses "skilful, clever, wise, prudent",^[12] and Barnhart to probably about 1200.^[4]

Semantic evolution

The bad sense came very early:^[8] "using cunning or underhand means; deceitful, wily" is recorded before 1200,^[6][12] and in Middle English sly words could be either wise words or deceptive ones.^[12] Chaucer used the word 18 times and Gower 22 times, mostly for "cunning, artful".^[16] The older approving sense survived into the 20th century in northern English dialects,^[15][12] where the word also had the form slee,^[17] and Merriam-Webster still records "shrewd, canny" as chiefly dialectal, quoting Burns.^[3] The sense "secret, stealthy" appears about 1440,^[6] and on the sly, in secret, from 1812.^[12][4] Johnson (1755) defined it as "meanly artful; secretly insidious; cunning".^[18] The milder sense "playfully mischievous, roguish" dates from 1764 in Etymonline and before 1771 in the OED.^[12][6] In slang sly came to mean illicit, especially in the Australian sly grog (1829),^[6][19] and slyboots, a sly person, is in the Dictionary of the Canting Crew of about 1698.^[19][12] A Scottish and American verb sly, to move stealthily, is recorded from 1825.^[6][10]

Timeline

• c. 1175 – skilful, clever, wise, in the Ormulum.^[6]
• before 1200 – cunning, deceitful, wily.^[6][12]
• 1297 – of things, skilfully made (obsolete by 1721).^[6]
• c. 1440 – secret, stealthy.^[6]
• c. 1698 – slyboots.^[19]
• 1755 – Johnson: "meanly artful; secretly insidious".^[18]
• 1764 – playfully artful, knowing.^[12]
• 1812 – on the sly.^[12][4]
• 1825 – verb, to move stealthily.^[6]
• 1829 – illicit, in sly grog.^[6]

Meanings

Adjective

1. Clever at getting one's way by deceit or secrecy; cunning, crafty: a sly old horse dealer.^[11][3][6]
2. Done in secret; furtive or stealthy: a sly glance at the clock.^[11][6]
3. Playfully mischievous or knowing; roguish: She answered with a sly grin.^[11][6]
4. (chiefly dialectal) Shrewd, canny, wise in practical matters.^[3][6][17]
5. on the sly: secretly.^[11][4]
6. (slang, chiefly Australian) Illicit, as in sly grog, illegally sold liquor.^[6][19]
7. (obsolete, 1297–1721) Made with skill; ingenious.^[6][3]

Verb

1. (Scottish and US) To move stealthily; to slink.^[10][3][6]

Word family

• slyly
• slyness
• unsly
• sly-grog
• slyboots

Related words

• slay
• sleight
• slaughter

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ Kurath, Hans; Kuhn, Sherman M.; Lewis, Robert E., eds. (1952–2001), Middle English Dictionary, Ann Arbor: University of Michigan Press; online edition ed. Frances McSparran et al. (2000–2018)
3. ^ a b c d e f Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
4. ^ a b c d e f Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
5. ^ a b c Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
6. ^ a b c d e f g h i j k l m n o p q r s t u v w x Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
7. ^ The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
8. ^ a b c d Hoad, T. F., ed. (1986), The Concise Oxford Dictionary of English Etymology, Oxford: Clarendon Press
9. ^ Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
10. ^ a b c d Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
11. ^ a b c d e Collins English Dictionary (2023), Glasgow: HarperCollins
12. ^ a b c d e f g h i j k l m Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
13. ^ a b Random House Webster's Unabridged Dictionary (1999), 2nd ed., New York: Random House
14. ^ Skeat, Walter W. (1911), A Concise Etymological Dictionary of the English Language, new ed., Oxford: Clarendon Press
15. ^ a b Ayto, John (2005), Word Origins: The Secret Histories of English Words from A to Z, 2nd ed., London: A & C Black
16. ^ Benson, Larry D., Glossarial Concordance to Middle English (Chaucer, Gower), Johns Hopkins University, github.com/jhu-digital-manuscripts/gcme
17. ^ a b Wright, Joseph, ed. (1898–1905), The English Dialect Dictionary, 6 vols., Oxford: Henry Frowde; via EDD Online 4.0, University of Innsbruck (CC BY 4.0)
18. ^ a b Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
19. ^ a b c d Green, Jonathon (2010), Green's Dictionary of Slang, London: Chambers; digital ed. 2016–, https://greensdictofslang.com