thinvsthinlyTell them apart

Quick tell: thin is a adjective, thinly is an adverb, so they fill different roles in a sentence.

Which to use

“thin” is an adjective and “thinly” is an adverb - they look or sound alike but fill different roles in a sentence.

#3,200
“thin” frequency rank
#20,513
“thinly” frequency rank
23713
confusion score

Side-by-Side Comparison

Feature thin thinly
Definition Having little thickness or extent from one surface to its opposite. In a thin, loose, or scattered manner; scantily; not thickly.

Where the eye mixes thin and thinly

Muted = shared; highlighted = the visual trap. They share 4 letters in sequence.

4 ch
thin
6 ch
thinly

Look-alike desk: thin vs thinly

These two trip readers on the page rather than in the ear: thin is /θɪn/ while thinly is /ˈθɪnli/. Spoken aloud the problem disappears. In writing it persists, because they differ by 2 extra letter(s) - “thin” sits inside “thinly”, and the parts of speech differ too (adjective vs adverb), which is usually the fastest check. Our composite confusion score for this pair is 23713, derived from the frequency rank of both members and their visual similarity.

thin is recorded at frequency rank #3,200, classified as anadj, pronounced /θɪn/. thinly is at rank #20,513, tagged as anadv, pronounced /ˈθɪnli/.

Glosses for this pair are partially populated in our dataset, but the full side-by-side definitions above should still guide you to the right choice.

With a confusion score of 23713, this pair ranks #407,297 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of thin vs thinly

Shared letters: hint. Private to "thin": -. Private to "thinly": ly.

"thin" · 4 letters · shape CCVC  ·  "thinly" · 6 letters · shape CCVCCV

Known mistypes of this pair

  • thinhtin · thhin · thinn · thni · tihn · tthin
  • thinlyhtinly · thhinly · thilny · thinlly · thinlyy · thinnly · thinyl · thnily

Frequently Asked Questions

Is swapping "thin" for "thinly" ever safe?
No - they are not even the same part of speech. "thin" is an adjective and "thinly" an adverb, so a sentence built for one is usually ungrammatical with the other.
Frequency check: "thin" vs "thinly" - which ranks higher?
"thin" is the more common of the two: it sits at frequency rank #3,200 in our English list, against #20,513 for "thinly". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

After this comparison

Eye-level mix-up between "thin" and "thinly" is sorted above. Next: full entries or other pairs that share a letter shape.

  • Full dictionary entry for "thin" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "thinly" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #407,297 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "thin" and "thinly" also get mixed up with nearby pairs, the highest-scored neighbour is "thickly vs thinly". Nearby pair
  • Recorded mistypes exist for at least one side of this pair, useful when a spell-checker or OCR lands on the wrong form. See mistypes

Confusion rank #407,297 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.

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

Source: FrequencyWords open word-frequency list