thirtyvsthornyWhat's the difference?

Quick tell: thirty is a num, thorny is an adjective, so they fill different roles in a sentence.

Which to use

“thirty” is a num and “thorny” is an adjective - they look or sound alike but fill different roles in a sentence.

#3,791
“thirty” frequency rank
#31,798
“thorny” frequency rank
35589
confusion score

Side-by-Side Comparison

Feature thirty thorny
Definition The cardinal number occurring after twenty-nine and before thirty-one, represented in Arabic numerals as 30. Having thorns or spines.

Where the eye mixes thirty and thorny

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

6 ch
thirty
6 ch
thorny

Why the eye confuses thirty with thorny

These two trip readers on the page rather than in the ear: thirty is /ˈθɜːti/ while thorny is /ˈθɔːni/. Spoken aloud the problem disappears. In writing it persists, because they share most of their letters but differ in 2 positions, and the parts of speech differ too (num vs adjective), which is usually the fastest check. Our composite confusion score for this pair is 35589, derived from the frequency rank of both members and their visual similarity.

thirty is recorded at frequency rank #3,791, classified as anum, pronounced /ˈθɜːti/. thorny is at rank #31,798, tagged as anadj, pronounced /ˈθɔːni/.

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 35589, this pair ranks #310,689 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.

Orthographic DNA of thirty vs thorny

Shared letters: hrty. Private to "thirty": i. Private to "thorny": no.

"thirty" · 6 letters · shape CCVCCV  ·  "thorny" · 6 letters · shape CCVCCV

Known mistypes of this pair

  • thirtyhtirty · thhirty · thirrty · thirtty · thirtyy · thiryt · thitry · thrity
  • thornyhtorny · thhorny · thonry · thornny · thornyy · thorrny · thoryn · throny

Frequently Asked Questions

Can "thirty" and "thorny" be used interchangeably?
No - they are not even the same part of speech. "thirty" is a num and "thorny" an adjective, so a sentence built for one is usually ungrammatical with the other.
In ordinary English text, does "thirty" or "thorny" show up more?
"thirty" is the more common of the two: it sits at frequency rank #3,791 in our English list, against #31,798 for "thorny". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

After this comparison

Visual near-miss handled. Browse the word pages or a neighbour when the next look-alike shows up.

  • Full dictionary entry for "thirty" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "thorny" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #310,689 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "thirty" and "thorny" also get mixed up with nearby pairs, the highest-scored neighbour is "thon vs thorny". 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 #310,689 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