beginning, commencement, first, outset, start, kickoff, starting time, offset

the time at which something begins; "They got an early start"

• birth — the time when something begins (especially life)
• incipiency, incipience — beginning to exist or to be apparent
• terminus a quo, starting point — earliest limiting point
• threshold — the starting point for a new state or experience

• point, point in time — a very short period of time