With exact observance of an appointed time or times; at the agreed or proper time; on time. (Now the usual sense.)

With precision or exactness; exactly, precisely, accurately; (occasionally also) at a precise or particular time; punctually. Obsolete.

In an invitation or appointment: Punctually, precisely (at the hour specified).

Originally U.S. colloquial. Not later than the specified or required time; punctually, promptly; in time (see phrases 3k(a)(ii)). Also in…

With reference to a specified time: exactly, precisely, to the minute; = sharp, adv. 1c.

on the dot: exactly on time; punctually. Cf. on the dot of at phrases 1c.

In prepositional phrases with of (a time), as at the dot of, from the dot of, on the dot of, etc.: at, from, etc., the exact time specified.

more than punctually.

transferred (from sense 2a). The time between two ticks of the clock; a moment, second, instant. colloquial. onor to the tick, exactly at the…