opening; beginning; commencement
Literally 'lid opening', used figuratively for the start or opening of an event, project, or period. Often implies the initial stage or the moment something begins.
The opening of the new fiscal year is next month.
I was present at the commencement of the project.
Standard kanji spelling; 蓋 means 'lid' and 開け means 'opening', together meaning 'opening the lid' or 'beginning'.
Variant using 明け (to open, to dawn) instead of 開け; less common but still seen.
Compound of 蓋 (futa, 'lid') and 開け (ake, 'opening'), from the verb 開ける (akeru, 'to open'). The figurative sense of 'beginning' comes from the image of opening a lid to reveal or start something.