caspase

noun

"caspase" is a 7-letter English headword indexed on PlainSpell.

The verdict

“caspase” is uncommon English (frequency #64,971 among 43,570 “C” headwords), classed as a noun. The kind of spelling people second-guess.

#64,971
frequency rank, English
43,570
“C” headwords

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - Any of several intracellular proteolytic enzymes that mediate apoptosis and pyroptosis.

Corpus desk

Index EN-caspase · caspase · English

caspase · rank #64,971 · 0 variants · 0 confusables

  • FREQ-RARE #64,971
  • LEN-LONG 7 letters
  • VOW-3 3 vowels
  • CONFUS-0 No pairs
  • VAR-0 0 variants
  • BOOK-DENSE 43,570
  • PHOTO-FINISH casebook

Nearest frequency peer: casebook (-1 rank slots)

Read with this headword: Spelling guide for this pattern

Desk codes from Wiktionary headword shape, FrequencyWords rank tier, confusable-pair count, generated misspelling depth, letter-cohort book size, and photo-finish peer. Not a difficulty grade.

Frequency neighbourhood for “caspase”

Lower corpus rank = more everyday usage (inverted bar length for readability)

corpus weight

What this shows Bars show where “caspase” sits against the nearest ranked English headwords in the FrequencyWords band, not a reprint of letter-browse containment.

Source FrequencyWords open word-frequency list As of May 6, 2026
Key facts for caspase
PropertyValue
Headwordcaspase
LanguageEnglish
Part of speechNoun
Letters7
Frequency rank#64,971
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Where “caspase” sits in English frequency

Every-word frequency runs from the handful of words we use constantly (left) to the long tail used once in a blue moon (right). caspase lands here:

#1#100#1K#10K#100K
← used constantlyrarely used →

Scale is logarithmic (each tick is 10× rarer). Source: FrequencyWords open word-frequency list.

Rare enough to double-check

caspase is uncommon English at frequency #64,971 among 43,570 “C” headwords, classed as anoun. Rarity is why readers land here mid-draft. Gloss: "Any of several intracellular proteolytic enzymes that mediate apoptosis and pyroptosis.".

Our edit-distance generator produced no likely misspellings for caspase, since its letter sequence doesn't invite the usual edit-distance slips. This entry stands alone in our confusable dataset, since nothing in our dataset looks or sounds close enough to cause mix-ups.

Etymologically, the entry records: Short for cysteine-aspartic acid protease. The correct English form is caspase, spelled C-A-S-P-A-S-E.

Definition

  1. 1
    Any of several intracellular proteolytic enzymes that mediate apoptosis and pyroptosis.

Etymology

Short for cysteine-aspartic acid protease.

Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA); frequency ordering uses the FrequencyWords open word-frequency list (2018 English corpus, MIT). See the methodology for how each field is sourced and updated.

PlainSpell is rendered directly from structured Wiktionary extracts and open word-frequency lists, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of May 6, 2026. Primary sources: Wiktionary (via kaikki.org) and FrequencyWords.

Frequently Asked Questions

How do you spell "caspase"?
"caspase" is spelled C-A-S-P-A-S-E.
What does "caspase" mean?
As a noun, "caspase" means: Any of several intracellular proteolytic enzymes that mediate apoptosis and pyroptosis.
What is the origin of the word "caspase"?
Short for cysteine-aspartic acid protease. See the full etymology section above for more details.
Is PlainSpell free to use?
Yes, PlainSpell is a completely free word reference. You can look up definitions, pronunciations, confusable pairs, homophones, and spelling corrections across 5 languages without any sign-up or subscription.

Similar English words by spelling shape

Same letter count and similar misspelling depth for "caspase", not the corpus desk frequency band.

Same letter count

Frequency-ranked English headwords with 7 letters (nearest by frequency rank).

Data Source

Wiktionary (via kaikki.org), licensed under CC BY-SA & GFDL. Word ordering uses an open word-frequency list; misspelling variants are generated by edit-distance from the correct headword.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list