Synonyms: epoch
Definition: a unit of geological time that is a subdivision of a period and is itself divided into ages
Similar words: geologic time, geological time
Definition: the time of the physical formation and development of the earth (especially prior to human history)
Definition: a period marked by distinctive character or reckoned from a fixed point or event
Similar words: time period, period, period of time
Definition: an amount of time
Usage: a time period of 30 years; hastened the period of time of his recovery; Picasso's blue period
Synonyms: epoch, date of reference
Definition: (astronomy) an arbitrarily fixed date that is the point in time relative to which information (as coordinates of a celestial body) is recorded
Similar words: date
Definition: the particular day, month, or year (usually according to the Gregorian calendar) that an event occurred
Usage: he tried to memorizes all the dates for his history class