Prolog

name

"prolog" is a 6-letter English headword indexed on PlainSpell.

The verdict

“Prolog” is uncommon English (frequency #63,908 among 4,417 “P” headwords), classed as a proper noun. The kind of spelling people second-guess.

#63,908
frequency rank, English
4,417
“P” headwords

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - A programming language developed in the 1970s for artificial intelligence and logic programming.

Corpus desk

Index EN-prolog · Prolog · English

Prolog · rank #63,908 · 0 variants · 0 confusables

  • FREQ-RARE #63,908
  • LEN-LONG 6 letters
  • VOW-2 2 vowels
  • CONFUS-0 No pairs
  • VAR-0 0 variants
  • BOOK-MID 4,417
  • PHOTO-FINISH prissy

Nearest frequency peer: prissy (-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 “Prolog”

Sparse band: bars invert rank so rarer forms read shorter

corpus weight

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

Source FrequencyWords open word-frequency list As of September 3, 2026
Key facts for Prolog
PropertyValue
HeadwordProlog
LanguageEnglish
Part of speechProper noun
Letters6
Frequency rank#63,908
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Long-tail rank of “Prolog” in English

Word frequency stretches from the small set of words we reach for constantly (left) out to the long tail barely used once in a while (right).Prologfalls in this rarity band:

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

Ticks step logarithmically, so each one marks a roughly tenfold drop in how often the word turns up. Rare peers in the same band: “prissy” (#63,907), “pretension” (#63,906), “prefab” (#63,905). Among 4,417 “P” headwords, “Prolog” is #63,908. Source: FrequencyWords open word-frequency list.

Rare enough to double-check

Prolog is uncommon English at frequency #63,908 among 4,417 “P” headwords, classed as aproper noun. Rarity is why readers land here mid-draft. Gloss: "A programming language developed in the 1970s for artificial intelligence and logic programming.".

No generated misspelling entries exist for Prolog in our index, since its letter pattern doesn't lend itself to common typo substitutions. This entry stands alone in our confusable dataset, which typically means the spelling is too distinctive to be mistaken for another word.

Etymologically, the entry records: From French Prolog, abbreviation of Programmation en Logique. The correct English form is Prolog, spelled P-R-O-L-O-G.

Definition

  1. 1
    A programming language developed in the 1970s for artificial intelligence and logic programming.

Recorded use

Wiktionary example

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

  1. Prolog has been used for many purposes, but its inventor, Alain Colmerauer, was interested in computational linguistics, and this remains a classic application for the language. Moreover, Prolog offers a number of tools which make life easier for computational linguists, and we are now going to start learning about one of the most useful of these: definit…

Etymology

From French Prolog, abbreviation of Programmation en Logique.

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 "Prolog"?
"Prolog" is spelled P-R-O-L-O-G.
What does "Prolog" mean?
As a proper noun, "Prolog" means: A programming language developed in the 1970s for artificial intelligence and logic programming.
What is the origin of the word "Prolog"?
From French Prolog, abbreviation of Programmation en Logique. 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 "Prolog", not the corpus desk frequency band.

Same letter count

Frequency-ranked English headwords with 6 letters (nearest by frequency rank).

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

Source: FrequencyWords open word-frequency list