sly

/slaɪ/

//slaɪ// adj

By · According to Wiktionary data (CC BY-SA) ·

"sly" is a 3-letter English headword indexed on PlainSpell.

The verdict

“sly” sits in 20 confusable pairs (corpus #17,246) as an adjective. The look-alike neighbours are the real trap.

#17,246
frequency rank, English
6,566
“S” headwords
20
confusable pairs

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - Artfully cunning; secretly mischievous; wily.

Corpus desk

Index EN-sly · sly · English

sly · rank #17,246 · 0 variants · 20 confusables

  • FREQ-MID #17,246
  • LEN-MID 3 letters
  • VOW-1 1 vowel
  • CONFUS-HIGH 20 pairs
  • VAR-0 0 variants
  • BOOK-DENSE 6,566
  • PHOTO-FINISH Slovakia

Nearest frequency peer: Slovakia (-1 rank slots)

Read with this headword: Spelling guide for this pattern

Desk codes from Wiktionary headword shape, FrequencyWords rank tier, confusable-pair count, generated misspelling depth, letter-cohort book size, and photo-finish peer. Not a difficulty grade.

Frequency neighbours of confusable “sly”

Peers at similar corpus weight, separate from look-alike pairs below

corpus weight

What this shows Bars place “sly” against nearest ranked English headwords, not a reprint of the confusable-pair desk.

Source FrequencyWords open word-frequency list As of September 3, 2026

Visual similarity to commonly confused words

How many letter changes separate each confused pair (Levenshtein distance, normalized).

sly vs so
33% similar
sly vs SS
0% similar
sly vs SP
0% similar

Source: PlainSpell confusable corpus (Wiktionary, CC BY-SA).

Key facts for sly
PropertyValue
Headwordsly
LanguageEnglish
Part of speechAdjective
IPA/slaɪ/
Letters3
Frequency rank#17,246
Misspellings tracked0
Confusable pairs20
SourceWiktionary (kaikki.org)

Corpus rank beside confusables of “sly”

This scale runs from the tiny cluster of words that carry ordinary speech (left) to the long tail of words almost nobody reaches for (right).slylands here:

#1#100#1K#10K#100K
← used constantlyrarely used →

The axis is logarithmic, with each marked tick roughly ten times rarer than the last. Same rarity band neighbours include “Slovakia” (#17,245), “smiley” (#17,247), “skepticism” (#17,244). Among 6,566 “S” headwords, “sly” is #17,246. Source: FrequencyWords open word-frequency list.

Easy to mix with look-alikes

The spelling risk for sly is neighbouring look-alikes ("so", "SS", …), not just typos; it is anadjective pronounced /slaɪ/. Frequency #17,246 among 6,566 “S” headwords. 4 recorded senses keep meaning in play.

No generated misspelling entries exist for sly in our index, typically a sign the spelling maps closely to how the word sounds. It also participates in 20 confusable-pair relationships, "so", "SS", "SP", and more, a pairing that trips writers up because the two words share enough sound or shape to blur together.

Etymologically, the entry records: From Middle English sly, sley, sleigh, sleiȝ, from Old Norse slǿgr (“sly, cunning”, literally “capable of hitting or striking”), from Proto-Germanic *slōgiz (“lively, agile, cunning, sly, striking”), from Proto-Indo-European *slak- (“to hit, throw”). Cognat… The correct English form is sly, spelled S-L-Y.

Definition

  1. 1
    Artfully cunning; secretly mischievous; wily.
  2. 2
    Dexterous in performing an action, so as to escape notice
  3. 3
    Done with, and marked by, artful and dexterous secrecy; subtle
  4. 4
    Light or delicate; slight; thin.

Etymology

From Middle English sly, sley, sleigh, sleiȝ, from Old Norse slǿgr (“sly, cunning”, literally “capable of hitting or striking”), from Proto-Germanic *slōgiz (“lively, agile, cunning, sly, striking”), from Proto-Indo-European *slak- (“to hit, throw”). Cognate with Icelandic slægur (“crafty, sly”), Norwegian Nynorsk sløg (“sly”). Related to sleight, slay. In all likelihood, however, unrelated with Saterland Frisian slau (“sly, crafty”), Dutch sluw (“sly, cunning”), Low German slu (“sly, cunning”), German schlau (“clever, crafty”). Doublet of sleight and slöjd

Synonyms

artfulcraftycunningknowingsharpshiftyshrewdslimsly as a foxwily

This word in other languages

astuto(Español)sournois(Français)schlau(Deutsch)esperto(Português)

Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA); frequency ordering uses the FrequencyWords open word-frequency list (2018 English corpus, MIT). See the methodology for how each field is sourced and updated.

Frequently Asked Questions

How do you spell "sly"?
"sly" is spelled S-L-Y. The IPA pronunciation is /slaɪ/.
What does "sly" mean?
As an adjective, "sly" means: Artfully cunning; secretly mischievous; wily.
What words are commonly confused with "sly"?
"sly" is commonly confused with "so", "SS", "SP". These words look or sound similar but have different meanings. PlainSpell provides detailed comparisons for each pair.
How do you pronounce "sly"?
The IPA (International Phonetic Alphabet) transcription for "sly" is /slaɪ/. Click the speaker icon on the pronunciation badge above to hear it spoken aloud where audio is available.
What is the origin of the word "sly"?
From Middle English sly, sley, sleigh, sleiȝ, from Old Norse slǿgr (“sly, cunning”, literally “capable of hitting or striking”), from Proto-Germanic *slōgiz (“lively, agile, cunning, sly, striking”), from Proto-Indo-European *slak- (“to hit, throw... See the full etymology section above for more details.
Is PlainSpell free to use?
Yes, PlainSpell is a completely free word reference. You can look up definitions, pronunciations, confusable pairs, homophones, and spelling corrections across 5 languages without any sign-up or subscription.

Similar English words by spelling shape

Same letter count and similar misspelling depth for "sly", not the corpus desk frequency band.

Same letter count

Frequency-ranked English headwords with 3 letters (nearest by frequency rank).

vid#17,267aft#17,285Pak#17,199NIC#17,191

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list