fissilevsfissureTell them apart

Quick tell: fissile is a adjective, fissure is a noun, so they fill different roles in a sentence.

Which to use

“fissile” is an adjective and “fissure” is a noun - they look or sound alike but fill different roles in a sentence.

#49,335
“fissile” frequency rank
#36,143
“fissure” frequency rank
85478
confusion score

Side-by-Side Comparison

Feature fissile fissure
Definition Able to be split. A long, narrow crack or opening made by breaking or splitting, especially in rock or earth.

Where the eye mixes fissile and fissure

Muted = shared; highlighted = the visual trap. They share 5 letters in sequence. fissile and fissure follow the identical consonant-vowel pattern (CVCCVCV). Same shape at a glance is often the real trap, independent of shared letters.

7 ch
fissile
7 ch
fissure

Look-alike desk: fissile vs fissure

These two trip readers on the page rather than in the ear: fissile is /ˈfɪsˌaɪ.əl/ while fissure is /ˈfɪʃ.ə/. 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 (adjective vs noun), which is usually the fastest check. Our composite confusion score for this pair is 85478, derived from the frequency rank of both members and their visual similarity.

fissile is recorded at frequency rank #49,335, classified as anadj, pronounced /ˈfɪsˌaɪ.əl/. fissure is at rank #36,143, tagged as anoun, pronounced /ˈfɪʃ.ə/.

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 85478, this pair ranks #10,335 of 530,003 scored English confusable pairs - among the most confusable pairs.

Orthographic DNA of fissile vs fissure

Shared letters: efis. Private to "fissile": l. Private to "fissure": ru.

"fissile" · 7 letters · shape CVCCVCV  ·  "fissure" · 7 letters · shape CVCCVCV

Known mistypes of this pair

  • fissile ← ffissile · fisile · fisisle · fissiel · fissille · fisslie · fsisile · ifssile
  • fissure ← ffissure · fissrue · fissuer · fissurre · fisure · fisusre · fsisure · ifssure

Frequently Asked Questions

Is swapping "fissile" for "fissure" ever safe?
No - they are not even the same part of speech. "fissile" is an adjective and "fissure" a noun, so a sentence built for one is usually ungrammatical with the other.
In ordinary English text, does "fissile" or "fissure" show up more?
"fissure" is the more common of the two: it sits at frequency rank #36,143 in our English list, against #49,335 for "fissile". 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 "fissile" and "fissure" is sorted above. Next: full entries or other pairs that share a letter shape.

  • Full dictionary entry for "fissile" with definition, IPA, and generated misspellings. Word entry
  • Full dictionary entry for "fissure" - compare definitions side by side with the headword page. Word entry
  • This pair ranks #10,335 of 530,003 scored English confusable pairs in this corpus vintage. Corpus statistics
  • "fissile" and "fissure" also get mixed up with nearby pairs, the highest-scored neighbour is "fissile vs fission". 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 #10,335 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