qubit
/ˈkjuːbɪt/
"qubit" is a 5-letter English headword indexed on PlainSpell.
The verdict
“qubit” is uncommon English (frequency #78,056 among 2,880 “Q” headwords), classed as a noun. The kind of spelling people second-guess.
- #78,056
- frequency rank, English
- 2,880
- “Q” headwords
According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - A quantum bit; the basic unit of quantum information described by a superposition of two states; a quantum bit in a quantum computer capable of being in a state of superposition; A binary qudit.
| Property | Value |
|---|---|
| Headword | qubit |
| Language | English |
| Part of speech | Noun |
| IPA | /ˈkjuːbɪt/ |
| Letters | 5 |
| Frequency rank | #78,056 |
| Misspellings tracked | 0 |
| Confusable pairs | 0 |
| Source | Wiktionary (kaikki.org) |
Where “qubit” sits in English frequency
Rare enough to double-check
qubit is uncommon English at frequency #78,056 among 2,880 “Q” headwords, classed as anoun, transcribed /ˈkjuːbɪt/. Rarity is why readers land here mid-draft. Gloss: "A quantum bit; the basic unit of quantum information described by a superposition of two states; a quantum bit in a quantum computer capable of being in a state of superposition; A binary qudit.".
We couldn't generate a plausible misspelling set for qubit, typically a sign the spelling maps closely to how the word sounds. 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: Blend of quantum + bit, a play on cubit (“historical unit of length”). Coined by American physicist Benjamin Schumacher in 1995. The correct English form is qubit, spelled Q-U-B-I-T.
Definition
- 1A quantum bit; the basic unit of quantum information described by a superposition of two states; a quantum bit in a quantum computer capable of being in a state of superposition; A binary qudit.
Etymology
Blend of quantum + bit, a play on cubit (“historical unit of length”). Coined by American physicist Benjamin Schumacher in 1995.
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); frequency ordering uses the FrequencyWords open word-frequency list (2018 English corpus, MIT). See the methodology for how each field is sourced and updated.
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Using “qubit”
The practical upshot for anyone who landed here from a spell-check.
- The one correct English spelling is Q-U-B-I-T - every other letter order is a misspelling in standard orthography.
- Say it as /ˈkjuːbɪt/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
- Browse more English words and confusable pairs in the same reference. English words
Other uncommon English words near this 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.