WordRel.com

• a period marked by distinctive character or reckoned from a fixed point or event

  synonym	era
  derivation	epochal
  hypernym	periodperiod of timetime period
  hyponym	agedayhistoric periodmodern era
  instance hyponym	Anno DominiCaliphateChristian eraCommon era

• a unit of geological time that is a subdivision of a period and is itself divided into ages

  holo part	geological periodperiod
  hypernym	geologic timegeological time
  instance hyponym	EoceneEocene epochGlacial epochHoloceneHolocene epochMioceneMiocene epochOligoceneOligocene epochPaleocenePaleocene epochPleistocenePleistocene epochPliocenePliocene epochRecentRecent epoch

• (astronomy) an arbitrarily fixed date that is the point in time relative to which information (as coordinates of a celestial body) is recorded

  synonym	date of reference
  domain topic	astronomyuranology
  hypernym	date