Which to use
“filly” is a noun and “fully” is an adverb - they look or sound alike but fill different roles in a sentence.
- #23,832
- “filly” frequency rank
- #1,366
- “fully” frequency rank
- 25198
- confusion score
Side-by-Side Comparison
| Feature | filly | fully |
|---|---|---|
| Definition | A young female horse. | In a full manner; without lack or defect; completely, entirely. |
Where the eye mixes filly and fully
Muted = shared; highlighted = the visual trap. They share 4 letters in sequence.
Visual trap between filly and fully
These two trip readers on the page rather than in the ear: filly is /ˈfɪli/ while fully is /ˈfʊli/. Spoken aloud the problem disappears. In writing it persists, because they differ by a single letter - i in “filly” becomes u in “fully”, and the parts of speech differ too (noun vs adverb), which is usually the fastest check. Our composite confusion score for this pair is 25198, derived from the frequency rank of both members and their visual similarity.
filly is recorded at frequency rank #23,832, classified as anoun, pronounced /ˈfɪli/. fully is at rank #1,366, tagged as anadv, pronounced /ˈfʊli/.
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 25198, this pair ranks #396,164 of 530,003 scored English confusable pairs - roughly mid-pack for confusability.
Orthographic DNA of filly vs fully
Shared letters: fly. Private to "filly": i. Private to "fully": u.
"filly" · 5 letters · shape CVCCV · "fully" · 5 letters · shape CVCCV
Known mistypes of this pair
Frequently Asked Questions
Is swapping "filly" for "fully" ever safe?
Which is more common, "filly" or "fully"?
Useful next steps
Pronunciation already separates them, if the page still looks alike, the dictionary links below settle it.
- Full dictionary entry for "filly" with definition, IPA, and generated misspellings. Word entry
- Full dictionary entry for "fully" - compare definitions side by side with the headword page. Word entry
- This pair ranks #396,164 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
- "filly" and "fully" also get mixed up with nearby pairs, the highest-scored neighbour is "feely vs filly". 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 #396,164 of 530,003 scored English pairs, corpus vintage 2026-09-03, not spelling advice.