Standard Lemma guide

mega-annum

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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  • /ˌmɛɡəˈænəm/

1

noun

Meaning 1

Synonym of megayear: a period of 1 million years.

Definition source: English Wiktionary via Wiktextract

Examples

  • Holonyms: petasecond < giga-annum, gigayear < exasecond
  • Meronyms: quectosecond < rontosecond < yoctosecond < zeptosecond < attosecond < femtosecond < picosecond < nanosecond < microsecond < millisecond < centisecond < decisecond < second < decasecond < minute < hectosecond < kilosecond < hour < day < week < megasecond < fortnight < month < year < gigasecond < century < kiloannum, kiloyear, millennium < terasecond

Meaning relationships

Synonyms: megayear

Antonyms: none provided

History

Etymology

From mega- + annum.