quadrillion

/kwɑˈdɹɪl.i.ən/

//kwɑˈdɹɪl.i.ən// num

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

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

The verdict

“quadrillion” is uncommon English (frequency #84,641 among 288 “Q” headwords), classed as a numeral. The kind of spelling people second-guess.

#84,641
frequency rank, English
288
“Q” headwords

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - A thousand trillion (logic: 1,000 × 1,000⁴): 1 followed by fifteen zeros, 10¹⁵.

Corpus desk

Index EN-quadrillion · quadrillion · English

quadrillion · rank #84,641 · 0 variants · 0 confusables

  • FREQ-RARE #84,641
  • LEN-MEGA 11 letters
  • VOW-5 5 vowels
  • CONFUS-0 No pairs
  • VAR-0 0 variants
  • BOOK-MID 288
  • PHOTO-FINISH quacking

Nearest frequency peer: quacking (-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 “quadrillion”

Sparse band: bars invert rank so rarer forms read shorter

corpus weight

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

Source FrequencyWords open word-frequency list As of September 3, 2026
Key facts for quadrillion
PropertyValue
Headwordquadrillion
LanguageEnglish
Part of speechNumeral
IPA/kwɑˈdɹɪl.i.ən/
Letters11
Frequency rank#84,641
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Long-tail rank of “quadrillion” in English

Every-word frequency runs from the handful of words we use constantly (left) to the long tail used once in a blue moon (right).quadrillionfalls 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: “quacking” (#84,640), “quilter” (#84,643), “Pushpa” (#84,638). Among 288 “Q” headwords, “quadrillion” is #84,641. Source: FrequencyWords open word-frequency list.

Rare enough to double-check

quadrillion is uncommon English at frequency #84,641 among 288 “Q” headwords, classed as anumeral, transcribed /kwɑˈdɹɪl.i.ən/. Rarity is why readers land here mid-draft. 2 senses are on record.

We couldn't generate a plausible misspelling set for quadrillion, and the word's spelling is regular enough that our generator found nothing worth flagging. No confusable counterpart is on file for this word, since its spelling is unusual enough that it doesn't cluster with a lookalike.

Etymologically, the entry records: From French quadrillion, from quadri- (“four”) + -illion. By surface analysis, quadr- + -illion. The correct English form is quadrillion, spelled Q-U-A-D-R-I-L-L-I-O-N.

Definition

  1. 1
    A thousand trillion (logic: 1,000 × 1,000⁴): 1 followed by fifteen zeros, 10¹⁵.
  2. 2
    A million trillion (logic: 1,000,000⁴): 1 followed by twenty-four zeros, 10²⁴.

Recorded use

Wiktionary examples

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

  1. A man named Chris Reynolds was credited $92 quadrillion USD on his paypal account, "This unexpected influx of wealth elevated him to the status of the richest person on the planet and the only quadrillionaire to have ever existed". Following this, after the man reported this error and it was fixed, "PayPal owned up to their mistake and thanked the richest…
  2. “I’m not sure I understand why we have to send a quadrillion-credit mission to another galaxy.” He looked fleetingly amused. “Quintillion... and we don’t have a choice, Harper. Any of us, really, but humanity especially.”

Etymology

From French quadrillion, from quadri- (“four”) + -illion. By surface analysis, quadr- + -illion.

Synonyms

10151024

This word in other languages

cuatrillón(Español)billiard(Français)Billiarde(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 "quadrillion"?
"quadrillion" is spelled Q-U-A-D-R-I-L-L-I-O-N. The IPA pronunciation is /kwɑˈdɹɪl.i.ən/.
What does "quadrillion" mean?
As a numeral, "quadrillion" means: A thousand trillion (logic: 1,000 × 1,000⁴): 1 followed by fifteen zeros, 10¹⁵.
How do you pronounce "quadrillion"?
The IPA (International Phonetic Alphabet) transcription for "quadrillion" is /kwɑˈdɹɪl.i.ən/. 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 "quadrillion"?
From French quadrillion, from quadri- (“four”) + -illion. By surface analysis, quadr- + -illion. 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 "quadrillion", not the corpus desk frequency band.

Same letter count

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

psychogenic#84,634Platteville#84,615physiognomy#84,608pericardium#84,605

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

Source: FrequencyWords open word-frequency list