Phrase guide

semimajor axis

noun · 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

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1

noun

Meaning 1

Half of the major axis of a circle or ellipse.

Definition source: English Wiktionary via Wiktextract

Topics: geometry, mathematics, sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

noun

Meaning 2

Half of the distances between the two branches of a hyperbola.

Definition source: English Wiktionary via Wiktextract

Topics: geometry, mathematics, sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

3

noun

Meaning 3

one-half the major axis of an ellipse; the distance from the center of an ellipse to one end

Definition source: Princeton WordNet 3.0

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

Broader terms: axis

History

Etymology

From semi- + major axis.

Across languages

Translations

7 source translations are retained for this English entry.

  • Chinese Mandarin: 半長軸 /半长轴 (bànchángzhóu) — half of the major axis of a circle or ellipse
  • French: demi-grand axe — half of the major axis of a circle or ellipse
  • German: Ellipsenhalbachse — half of the major axis of a circle or ellipse
  • German: Halbachse f der Ellipse — half of the major axis of a circle or ellipse
  • Japanese: 半長軸 (hanchōjiku) — half of the major axis of a circle or ellipse
  • Turkish: ana eksen — half of the major axis of a circle or ellipse
  • Turkish: büyük eksen — half of the major axis of a circle or ellipse