noun
starting time of work; opening time
Refers to the time when work or school officially begins for the day.
始業時間は9時です。
The starting time of work is 9 o'clock.
始業時間に遅れないように早く家を出た。
I left home early so as not to be late for the start of work.
Compound of 始業 (beginning work/school) and 時間 (time).