ep·och (?p‘?k, ?‘p?k‘) pronunciation
n.

    1. A particular period of history, especially one considered remarkable or noteworthy.
    2. A notable event that marks the beginning of such a period. See synonyms at period.
  2. A unit of geologic time that is a division of a period.
  3. Astronomy. An instant in time that is arbitrarily selected as a point of reference.