fillvsfishConfusable pair

Quick tell: fill is a verb, fish is a noun, so they fill different roles in a sentence.

Which to use

“fill” is a verb and “fish” is a noun - they look or sound alike but fill different roles in a sentence.

#2,297
“fill” frequency rank
#1,339
“fish” frequency rank
3636
confusion score

Side-by-Side Comparison

Feature fill fish
Definition To make full A typically cold-blooded vertebrate animal that lives in water, moving with the help of fins and breathing with gills.

Where the eye mixes fill and fish

Muted = shared; highlighted = the visual trap. They share 2 letters in sequence.

4 ch
fill
4 ch
fish

Visual trap between fill and fish

These two trip readers on the page rather than in the ear: fill is /fɪl/ while fish is /ˈfɪʃ/. 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 (verb vs noun), which is usually the fastest check. Our composite confusion score for this pair is 3636, derived from the frequency rank of both members and their visual similarity.

fill is recorded at frequency rank #2,297, classified as averb, pronounced /fɪl/. fish is at rank #1,339, tagged as anoun, pronounced /ˈfɪʃ/.

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 3636, this pair ranks #521,491 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of fill vs fish

Shared letters: fi. Private to "fill": l. Private to "fish": hs.

"fill" · 4 letters · shape CVCC  ·  "fish" · 4 letters · shape CVCC

Known mistypes of this pair

  • fillffill · flil · ifll
  • fishffish · fihs · fishh · fissh · fsih · ifsh

Frequently Asked Questions

Can "fill" and "fish" be used interchangeably?
No - they are not even the same part of speech. "fill" is a verb and "fish" a noun, so a sentence built for one is usually ungrammatical with the other.
Which is more common, "fill" or "fish"?
"fish" is the more common of the two: it sits at frequency rank #1,339 in our English list, against #2,297 for "fill". The two are close in frequency, so neither is a safe default; check the meaning rather than guessing.

Useful next steps

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

  • Full dictionary entry for "fill" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "fish" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #521,491 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "fill" and "fish" also get mixed up with nearby pairs, the highest-scored neighbour is "fish vs foh". 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 #521,491 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