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quintillion

/kwɪnˈtɪljən/number, noun

quintillion is spelled Q-U-I-N-T-I-L-L-I-O-N: 11 letters. It appears about once in every 16 million words in written English, the 121,279th most frequent word form (wordfreq, 2021 data). As a number, quintillion means “A billion billion: 1 followed by eighteen zeros, 10¹⁸; one million million million” (English Wiktionary, September 2026).

How many letters and syllables are in quintillion?

Letters11: Q-U-I-N-T-I-L-L-I-O-N
In writingabout once in every 16 million words; the 121,279th most frequent word form
Wrong spellings searchednone measured in search

Sources: letters and syllables from the English Wiktionary's hyphenation or pronunciation; written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media).

How common is quintillion?

Quintillion appears about once in every 16 million words in written English, the 121,279th most frequent word form in the list.

Source: written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media).

How do you pronounce quintillion?

  • /kwɪnˈtɪljən/

Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract). Recordings: En-us-quintillion.ogg, Wikimedia Commons (author and licence on each file's page).

Forms of quintillion

  • quintillions plural

Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).

What does quintillion mean?

The meanings the English Wiktionary records, quoted as written there (source below).

number

  1. 1

    BritishUSA billion billion: 1 followed by eighteen zeros, 10¹⁸; one million million million.

  2. 2

    AustraliaUKdatedA million quadrillion: 1 followed by 30 zeros, 10³⁰.

  3. 3

    colloquialAn unspecified very large number.

    Near-synonyms: gazillion; see also Thesaurus:zillion

noun

  1. 1

    slangAny very large number, exceeding normal description.

Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).

Quintillion in Spanish, French, German and Portuguese

LanguageWords
Frenchtrillion, milliard de milliards (a billion billion, 1018 – see also trillion), quintillion (a million quadrillion, 1030 – see also nonillion), milliard, milliards, million (any very large number)
GermanTrillion (a billion billion, 1018 – see also trillion), Quintillion, Quinquillion (a million quadrillion, 1030 – see also nonillion)
Portuguesetrilião m quintilhão (a billion billion, 1018 – see also trillion), quintilião, nonilhão (a million quadrillion, 1030 – see also nonillion), zilhão (any very large number)
Spanishtrillón, quintillón (a billion billion, 1018 – see also trillion)

Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract). Translations are Wiktionary's, by sense; a linked word has its own PlainSpell page.

Where does quintillion come from?

From French quintillion. By surface analysis, quint- (“five”) + -illion.

Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).

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