brainbox

/ˈbɹeɪn(ˌ)bɒks/

//ˈbɹeɪn(ˌ)bɒks// noun

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

"brainbox" is a 8-letter English headword indexed on PlainSpell.

The verdict

“brainbox” is uncommon English (outside the top frequency list), classed as a noun. The kind of spelling people second-guess.

Unranked
below top-frequency English
8
letters

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - The cavity of the skull in which the brain is contained.

Corpus desk

Index EN-brainbox · brainbox · English

brainbox · unranked · 0 variants · 0 confusables

  • FREQ-UNRANKED Unranked
  • LEN-LONG 8 letters
  • VOW-3 3 vowels
  • CONFUS-0 No pairs
  • VAR-0 0 variants
  • BOOK-THIN "B" thin
  • PHOTO-UNK Peer pending

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.

Key facts for brainbox
PropertyValue
Headwordbrainbox
LanguageEnglish
Part of speechNoun
IPA/ˈbɹeɪn(ˌ)bɒks/
Letters8
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Where “brainbox” sits in English frequency

brainboxranks outside the top 100,000 English headwords, in the long tail of specialist, archaic, or seldom-used vocabulary, exactly the territory where a reader stops mid-sentence to double-check spelling.

Beyond rank #100,000. Source: FrequencyWords open word-frequency list.

Rare enough to double-check

brainbox is uncommon English outside the top frequency list, classed as anoun, transcribed /ˈbɹeɪn(ˌ)bɒks/. Rarity is why readers land here mid-draft. 3 senses are on record.

No generated misspelling entries exist for brainbox in our index, since its letter pattern doesn't lend itself to common typo substitutions. This headword has no recorded confusable partner, suggesting its spelling stands apart enough that readers rarely confuse it with something else.

Etymologically, the entry records: From brain + box. The correct English form is brainbox, spelled B-R-A-I-N-B-O-X.

Definition

  1. 1
    The cavity of the skull in which the brain is contained.
  2. 2
    The skull; the head.
  3. 3
    A very intelligent person.

Recorded use

Wiktionary examples

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

  1. Holonyms: skull, cranium < head
  2. The compromise was to use as much of the skull as possible by pushing the eyes in towards the centre, and relegating the brain box to the rear.

Etymology

From brain + box.

Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA). See the methodology for how each field is sourced and updated.

Frequently Asked Questions

How do you spell "brainbox"?
"brainbox" is spelled B-R-A-I-N-B-O-X. The IPA pronunciation is /ˈbɹeɪn(ˌ)bɒks/.
What does "brainbox" mean?
As a noun, "brainbox" means: The cavity of the skull in which the brain is contained.
How do you pronounce "brainbox"?
The IPA (International Phonetic Alphabet) transcription for "brainbox" is /ˈbɹeɪn(ˌ)bɒks/. 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 "brainbox"?
From brain + box. 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.

What to do next

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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