sly

adjective

ˈslī How to pronounce sly (audio)
slyer also slier ˈslī(-ə)r How to pronounce sly (audio) ; slyest also sliest ˈslī-əst How to pronounce sly (audio)
Synonyms of sly
1
chiefly dialectal
a
: wise in practical affairs
b
: displaying cleverness : ingenious
2
a
: clever in concealing one's aims or ends : furtive
b
: lacking in straightforwardness and candor : dissembling
3
: lightly mischievous : roguish
a sly jest
slyly adverb
or less commonly slily
She slyly evaded the question.
slyness noun
see also:
on the sly

Synonyms of sly

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sly, cunning, crafty, wily, tricky, foxy, artful, slick mean attaining or seeking to attain one's ends by guileful or devious means.

sly implies furtiveness, lack of candor, and skill in concealing one's aims and methods.

a sly corporate raider

cunning suggests the inventive use of sometimes limited intelligence in overreaching or circumventing.

the cunning fox avoided the trap

crafty implies cleverness and subtlety of method.

a crafty lefthander

wily implies skill and deception in maneuvering.

the wily fugitive escaped the posse

tricky is more likely to suggest shiftiness and unreliability than skill in deception and maneuvering.

a tricky political operative

foxy implies a shrewd and wary craftiness usually involving devious dealing.

a foxy publicity man planting stories

artful implies indirectness in dealing and often connotes sophistication or cleverness.

elicited the information by artful questioning

slick emphasizes smoothness and guile.

slick operators selling time-sharing

Examples of sly in a Sentence

the movie pairs a sly, dissembling ex-con with an upstanding, straight-arrow cop why, you sly fellow! I had no idea you were planning my birthday party
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
This argument made by the unknown soldier—which included a sly criticism of the USSR—affected how the war-crazy Zinn was starting to reassess the entire operation. — Literary Hub, 12 Aug. 2026 The men exude contentious authority in various ways, from the grandee’s circumspect command and Uncle Jeb’s sly omniscience to the mechanic’s viperish resentment and Billy’s acerbic flirtation. — Richard Brody, New Yorker, 11 Aug. 2026 The camera is in position to see Cena’s sly smile and taps on Gunther’s forearm just so. — Darren Cooper, Forbes.com, 23 July 2026 Nancy Lemann, a New Orleans native, writes about the South with deep love and sly humor, and this book has the feel of a long dinner conversation with a very smart, very funny friend. — Amanda Eyre Ward, Travel + Leisure, 20 July 2026 See All Example Sentences for sly

Word History

Etymology

Middle English sleighe, sli, from Old Norse slœgr; akin to Old English slēan to strike — more at slay

First Known Use

13th century, in the meaning defined at sense 1a

Time Traveler
The first known use of sly was in the 13th century

Phrases Containing sly

Rhymes for sly

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Browse Nearby Words

SLW
sly
slyboots
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Cite this Entry

“Sly.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sly. Accessed 17 Aug. 2026.

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Kids Definition

sly

adjective
ˈslī How to pronounce sly (audio)
slier or slyer ˈslī(-ə)r How to pronounce sly (audio) ; sliest or slyest ˈslī-əst How to pronounce sly (audio)
1
a
: clever at hiding one's goals or purpose
b
: tending to secrecy or concealment
2
: lightly mischievous
a sly smile
slyly adverb
slyness noun

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