An Epoch

1. A particular period of history, especially one considered noteworthy or remarkable.
2. A notable event which marks the beginning of such a period.
3. (astronomy) A precise instant of time that is used as a point of reference.
4. (computing) Uses in computing.
   1. A precise instant of time that is used as a point of reference (e.g., January 1, 1970, 00:00:00 UTC).
   2. One complete presentation of the training data set to an iterative machine learning algorithm; generation.
5. (geology) A unit of geologic time subdividing a period into smaller parts.

Synonyms

• (particular period in history): age, era (only in general usage; in geology the words age, epoch, and era have specific meanings)