Standard Lemma guide

septillion

num · 3 senses · updated from the 2026-07-25 local source snapshot

Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.

Sound

Pronunciation

Each Play button uses your device's default local English voice, or a natural local fallback. The selected voice name appears after playback. This is synthesized speech, not a source recording.

  • /sɛpˈtɪljən/
  • US: Recorded audio is listed in the source snapshot.
  • rhymes with -ɪljən

1

num

Meaning 1

A trillion trillion: 1 followed by 24 zeros, 1024.

Definition source: English Wiktionary via Wiktextract

Usage: US

Qualifier: modern British & Australian; short scale; modern British & Australian; short scale

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

num

Meaning 2

A billion quintillion: 1 followed by 42 zeros, 1042.

Definition source: English Wiktionary via Wiktextract

Qualifier: dated British & Australian; long scale; dated British & Australian; long scale

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

3

noun

Meaning 3

the number that is represented as a one followed by 24 zeros

Definition source: Princeton WordNet 3.0

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

Broader terms: large integer

History

Etymology

From French septillion, from sept- (“seven”) + -illion. By surface analysis, sept- + -illion.

Across languages

Translations

29 source translations are retained for this English entry.

  • Armenian: սեպտիլիոն (septilion) — a trillion trillion, 1024 — see also quadrillion
  • Armenian: քառիլիոն (kʻaṙilion) — a trillion trillion, 1024 — see also quadrillion
  • Catalan: quadrilió — a trillion trillion, 1024 — see also quadrillion
  • Esperanto: kvariliono — a trillion trillion, 1024 — see also quadrillion
  • Finnish: kvadriljoona — a trillion trillion, 1024 — see also quadrillion
  • French: quatrillion — a trillion trillion, 1024 — see also quadrillion
  • German: Quadrillion — a trillion trillion, 1024 — see also quadrillion
  • Hungarian: kvadrillió — a trillion trillion, 1024 — see also quadrillion
  • Icelandic: kvaðrilljón — a trillion trillion, 1024 — see also quadrillion
  • Italian: quattrilione — a trillion trillion, 1024 — see also quadrillion
  • Japanese: 一秭 (ichijo/isshi) — a trillion trillion, 1024 — see also quadrillion
  • Malay: septilion — a trillion trillion, 1024 — see also quadrillion
  • Polish: kwadrylion — a trillion trillion, 1024 — see also quadrillion
  • Portuguese: quatrilião — a trillion trillion, 1024 — see also quadrillion
  • Portuguese: quadrilião — a trillion trillion, 1024 — see also quadrillion
  • Portuguese: septilhão — a trillion trillion, 1024 — see also quadrillion
  • Russian: септиллио́н (septillión) — a trillion trillion, 1024 — see also quadrillion
  • Spanish: cuatrillón — a trillion trillion, 1024 — see also quadrillion
  • Spanish: septillón — a trillion trillion, 1024 — see also quadrillion
  • Swedish: kvadriljon — a trillion trillion, 1024 — see also quadrillion
  • Welsh: septiliwn — a trillion trillion, 1024 — see also quadrillion
  • Esperanto: sepiliono — a billion quintillion, 1042 — see also tredecillion
  • Finnish: septiljoona — a billion quintillion, 1042 — see also tredecillion
  • German: Septillion — a billion quintillion, 1042 — see also tredecillion
  • Italian: settilione — a billion quintillion, 1042 — see also tredecillion
  • Japanese: 百正 (hyaku-sei) — a billion quintillion, 1042 — see also tredecillion
  • Portuguese: septilião — a billion quintillion, 1042 — see also tredecillion
  • Spanish: septillón — a billion quintillion, 1042 — see also tredecillion
  • Swedish: septiljon — a billion quintillion, 1042 — see also tredecillion