Which to use
“tern” is a noun and “thru” is a preposition - they look or sound alike but fill different roles in a sentence.
- #40,923
- “tern” frequency rank
- #9,266
- “thru” frequency rank
- 50189
- confusion score
Side-by-Side Comparison
| Feature | tern | thru |
|---|---|---|
| Definition | Any of various seabirds of the subfamily Sterninae (of the family Laridae) that are similar to gulls but are smaller and have a forked tail. | Nonstandard spelling of through. |
Where the eye mixes tern and thru
Muted = shared; highlighted = the visual trap. They share 2 letters in sequence. tern (CVCC) and thru (CCCV) run the same length but a different consonant-vowel pattern - the shape difference is usually the fastest tell.
Look-alike desk: tern vs thru
These two trip readers on the page rather than in the ear: tern is /tɜːn/ while thru is /θɹuː/. 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 (noun vs preposition), which is usually the fastest check. Our composite confusion score for this pair is 50189, derived from the frequency rank of both members and their visual similarity.
tern is recorded at frequency rank #40,923, classified as anoun, pronounced /tɜːn/. thru is at rank #9,266, tagged as aprep, pronounced /θɹuː/.
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 50189, this pair ranks #176,546 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.
Orthographic DNA of tern vs thru
Shared letters: rt. Private to "tern": en. Private to "thru": hu.
"tern" · 4 letters · shape CVCC · "thru" · 4 letters · shape CCCV
Known mistypes of this pair
Frequently Asked Questions
Is swapping "tern" for "thru" ever safe?
In ordinary English text, does "tern" or "thru" show up more?
Useful next steps
Pronunciation already separates them, if the page still looks alike, the dictionary links below settle it.
- Full dictionary entry for "tern" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "thru" - compare definitions side by side with the headword page. Word entry
- This pair ranks #176,546 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
- "tern" and "thru" also get mixed up with nearby pairs, the highest-scored neighbour is "tern vs Thun". 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 #176,546 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.