Refers to the start or opening of something, often used in a somewhat literary or formal context.
It was an event that heralded the beginning of a new era.
Used in a somewhat elevated or philosophical sense to refer to the advancement of civilization or enlightenment.
Human civilization rests on the accumulation of a long history.
open out; spread out; become clear · improve; look brighter; open up · develop; modernize; advance · be sensible; be understanding; be enlightened · open to traffic; become accessible · become built-up; become populous; become bustling
Derived from the verb 開ける (ひらける, 'to open up, become civilized'). The noun form 開け nominalizes the verb stem, carrying the sense of 'opening' or 'becoming enlightened'.