- epoch
- 1610s, "point marking the start of a new period in time" (e.g. the founding of Rome, the birth of Christ, the Hegira), from M.L. epocha, from Gk. epokhe "stoppage, fixed point of time," from epekhein "to pause, take up a position," from epi- "on" + ekhein "to hold." Transferred sense of "a period of time" is 1620s; geological usage (not a precise measurement) is from 1802. Related: Epochal.