6. Age, epoch, era, period all refer to an extent of time. Age usually implies a considerable extent of time, especially one associated with a dominant personality, influence, characteristic, or institution: the age of chivalry. Epoch and era are often used interchangeably to refer to an extent of time characterized by changed conditions and new undertakings: an era ( or epoch ) of invention. epoch sometimes refers especially to the beginning of an era: the steam engine—an epoch in technology. A period may be long or short, but usually has a marked condition or feature: the glacial period; a period of expansion.

Ag.E.

abbreviation for