quadrillion

Name: quadrillion, English Word Data
Creator: Wiktionary
License: https://creativecommons.org/licenses/by-sa/4.0/

/kwɑˈdɹɪl.i.ən/

//kwɑˈdɹɪl.i.ən// num

By PlainSpell Editorial Team · According to Wiktionary data (CC BY-SA) · analyzed May 6, 2026

The verdict

“quadrillion” is an uncommon English word, ranked #84,641 in English word frequency and used as a numeral.

#84,641
frequency rank, English: 11
letters

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - A thousand trillion (logic: 1,000 × 1,000⁴): 1 followed by fifteen zeros, 10¹⁵.

Key facts for quadrillion
Property	Value
Headword	quadrillion
Language	English
Part of speech	Numeral
IPA	/kwɑˈdɹɪl.i.ən/
Letters	11
Frequency rank	#84,641
Misspellings tracked	0
Confusable pairs	0
Source	Wiktionary (kaikki.org)

Where “quadrillion” sits in English frequency

Every-word frequency runs from the handful of words we use constantly (left) to the long tail used once in a blue moon (right). quadrillion lands here:

#84,641

#1#100#1K#10K#100K

← used constantlyrarely used →

Scale is logarithmic (each tick is 10× rarer). Source: FrequencyWords open word-frequency list.

Spelling & Dictionary Insight

The English entry for quadrillion is 11 letters long, classified as a numeral, and transcribed in the International Phonetic Alphabet as /kwɑˈdɹɪl.i.ən/. Corpus data places it at rank #84,641 in overall English word frequency, marking it as uncommon enough that many writers pause before typing it. Wiktionary records 2 distinct senses for this headword, so context determines which meaning a reader should apply.

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

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.

Using “quadrillion”

The practical upshot for anyone who landed here from a spell-check.

The one correct English spelling is Q-U-A-D-R-I-L-L-I-O-N - every other letter order is a misspelling in standard orthography.
Say it as /kwɑˈdɹɪl.i.ən/ (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

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.