black box
"black-box" is a 8-letter English headword indexed on PlainSpell.
The verdict
“black box” is uncommon English (outside the top frequency list), classed as a noun. The kind of spelling people second-guess.
- Unranked
- below top-frequency English
- 9
- letters
According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - A flight recorder; the brightly colored cockpit voice recorders and flight data recorders in an aircraft designed to aid in determining the cause of an accident.
Corpus desk
Index EN-black-box · black box · English
black box · unranked · 0 variants · 0 confusables
- FREQ-UNRANKED Unranked
- LEN-LONG 9 letters
- VOW-2 2 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.
| Property | Value |
|---|---|
| Headword | black box |
| Language | English |
| Part of speech | Noun |
| Letters | 9 |
| Misspellings tracked | 0 |
| Confusable pairs | 0 |
| Source | Wiktionary (kaikki.org) |
Long-tail rank of “black box” in English
Rare enough to double-check
black box is uncommon English outside the top frequency list, classed as anoun. Rarity is why readers land here mid-draft. 6 senses are on record.
We couldn't generate a plausible misspelling set for black box, a straightforward case of a spelling with little room for common typos. This entry stands alone in our confusable dataset, which tends to mean the word is visually distinctive enough to stand on its own.
Etymologically, the entry records: * Since c. 1945 in both main senses (that is, event recorders and objects with unknown innards), which are historically related to each other; for details, see black box § History and flight recorder § Terminology. * (a type of theater): Such theaters are o… The correct English form is black box, spelled B-L-A-C-K- -B-O-X.
Definition
- 1A flight recorder; the brightly colored cockpit voice recorders and flight data recorders in an aircraft designed to aid in determining the cause of an accident.
- 2Any similar device on motor vehicles, such as rail event recorders and ship trip recorders.
- 3A theoretical construct or device with known input and output characteristics but unknown method of operation.
- 4A device used in phreaking that prevents the calling party from being billed for the call placed.
- 5A type of theater characterized by a lack of decoration or complex mechanisms.
- 6Synonym of football (“the leather briefcase containing classified nuclear war plans which is always near the US President”)
Recorded use
Wiktionary examplesThese source excerpts show how black box appears in context. They illustrate usage; the definition above remains the entry’s reference meaning.
scrutinizing all utterances recorded by the black box
the pilothouse's analogue of an airliner's black box
Etymology
* Since c. 1945 in both main senses (that is, event recorders and objects with unknown innards), which are historically related to each other; for details, see black box § History and flight recorder § Terminology. * (a type of theater): Such theaters are often painted black.
This word in other languages
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.