endothermic

/ˌɛndəʊˈθəːmɪk/

//ˌɛndəʊˈθəːmɪk// adj

By · According to Wiktionary data (CC BY-SA) ·

"endothermic" is a 11-letter English headword indexed on PlainSpell.

The verdict

“endothermic” is uncommon English (frequency #89,328 among 2,246 “E” headwords), classed as an adjective. The kind of spelling people second-guess.

#89,328
frequency rank, English
2,246
“E” headwords

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - Of a chemical reaction that absorbs heat energy from its surroundings.

Corpus desk

Index EN-endothermic · endothermic · English

endothermic · rank #89,328 · 0 variants · 0 confusables

  • FREQ-RARE #89,328
  • LEN-MEGA 11 letters
  • VOW-4 4 vowels
  • CONFUS-0 No pairs
  • VAR-0 0 variants
  • BOOK-MID 2,246
  • PHOTO-FINISH energising

Nearest frequency peer: energising (+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.

Long-tail ranks near “endothermic”

Sparse band: bars invert rank so rarer forms read shorter

corpus weight

What this shows Long-tail view: where “endothermic” sits against similarly uncommon English ranks.

Source FrequencyWords open word-frequency list As of September 3, 2026
Key facts for endothermic
PropertyValue
Headwordendothermic
LanguageEnglish
Part of speechAdjective
IPA/ˌɛndəʊˈθəːmɪk/
Letters11
Frequency rank#89,328
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Long-tail rank of “endothermic” in English

This scale runs from the tiny cluster of words that carry ordinary speech (left) to the long tail of words almost nobody reaches for (right).endothermicfalls in this rarity band:

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

Scale is logarithmic (each tick is 10× rarer). Rare peers in the same band: “energising” (#89,329), “Elwes” (#89,326), “enthusiasms” (#89,331). Among 2,246 “E” headwords, “endothermic” is #89,328. Source: FrequencyWords open word-frequency list.

Rare enough to double-check

endothermic is uncommon English at frequency #89,328 among 2,246 “E” headwords, classed as anadjective, transcribed /ˌɛndəʊˈθəːmɪk/. Rarity is why readers land here mid-draft. 2 senses are on record.

Our edit-distance generator produced no likely misspellings for endothermic, suggesting the orthography follows predictable English patterns. Our confusable-pair dataset has no match for it, since no other headword is close enough in sound or shape to pair with it.

Etymologically, the entry records: Borrowed from French endothermique, from endo- (“inside”) + thermique (“of heat”), both ultimately from Ancient Greek. By surface analysis, endo- + -thermic. The correct English form is endothermic, spelled E-N-D-O-T-H-E-R-M-I-C.

Definition

  1. 1
    Of a chemical reaction that absorbs heat energy from its surroundings.
  2. 2
    Of an animal whose body temperature is regulated by internal factors.

Recorded use

Wiktionary example

These source excerpts show how endothermic appears in context. They illustrate usage; the definition above remains the entry’s reference meaning.

  1. These can be differentiated on a thermal scan where an endothermic transition indicates enantiotropes and an exothermic transition indicates monotropes .

Etymology

Borrowed from French endothermique, from endo- (“inside”) + thermique (“of heat”), both ultimately from Ancient Greek. By surface analysis, endo- + -thermic.

This word in other languages

endothermique(Français)endotherm(Deutsch)

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.

Frequently Asked Questions

How do you spell "endothermic"?
"endothermic" is spelled E-N-D-O-T-H-E-R-M-I-C. The IPA pronunciation is /ˌɛndəʊˈθəːmɪk/.
What does "endothermic" mean?
As an adjective, "endothermic" means: Of a chemical reaction that absorbs heat energy from its surroundings.
How do you pronounce "endothermic"?
The IPA (International Phonetic Alphabet) transcription for "endothermic" is /ˌɛndəʊˈθəːmɪk/. Click the speaker icon on the pronunciation badge above to hear it spoken aloud where audio is available.
What is the origin of the word "endothermic"?
Borrowed from French endothermique, from endo- (“inside”) + thermique (“of heat”), both ultimately from Ancient Greek. By surface analysis, endo- + -thermic. 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 "endothermic", not the corpus desk frequency band.

Same letter count

Frequency-ranked English headwords with 11 letters (nearest by frequency rank).

enthusiasms#89,331electorally#89,321elderflower#89,320euphemistic#89,338

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

Source: FrequencyWords open word-frequency list