Standard Lemma guide

sesquiannual

adj · 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

adj

Meaning 1

Occurring once every one and a half years (i.e. once every 18 months).

Definition source: English Wiktionary via Wiktextract

Usage: not-comparable

Examples

  • 1979, R. E. Meyer, Sesquiannual Report – April 1977-September 1978, Fossil Energy Division/DOE (DOE/W-7405-eng–26-1; cited in Surface Phenomena in Enhanced Oil Recovery (2013, →ISBN, page 718)
  • 1990, Sesquiannual Meeting of the American Society for Rickettsiology and Rickettsial Diseases; 8 (the society holds meetings roughly every 1.5 years, e.g. September 1989, May 1991, and September 1992)

Meaning relationships

Synonyms: none provided

Antonyms: none provided

History

Etymology

From sesqui- + annual.