Phrase guide

triangular number

noun · 1 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

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1

noun

Meaning 1

Any integer that is the sum of n natural numbers from 1 to n.

Definition source: English Wiktionary via Wiktextract

Topics: mathematics, sciences

Examples

  • Ten is a triangular number being the sum of 1, 2, 3, and 4.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

History

Etymology

No etymology was provided for this word.

Across languages

Translations

13 source translations are retained for this English entry.

  • Chinese Mandarin: 三角形數 /三角形数 (sānjiǎoxíngshù) — an integer which is the sum of n natural numbers
  • Dutch: driehoeksgetal — an integer which is the sum of n natural numbers
  • Esperanto: triangula nombro — an integer which is the sum of n natural numbers
  • Finnish: kolmioluku — an integer which is the sum of n natural numbers
  • German: Dreieckszahl — an integer which is the sum of n natural numbers
  • Hungarian: háromszögszám — an integer which is the sum of n natural numbers
  • Italian: numero triangolare — an integer which is the sum of n natural numbers
  • Japanese: 三角数 (sankaku-sū) — an integer which is the sum of n natural numbers
  • Latin: numerus triangularis — an integer which is the sum of n natural numbers
  • Polish: liczba trójkątna — an integer which is the sum of n natural numbers
  • Russian: треуго́льное число́ (treugólʹnoje čisló) — an integer which is the sum of n natural numbers
  • Spanish: número triangular — an integer which is the sum of n natural numbers
  • Tagalog: bilang na tatsihain — an integer which is the sum of n natural numbers