Wiktionary
at a time
adv. 1 In a single, continuous period of time. 2 Simultaneously at each occurrence (of some action).
WordNet
at a time
adv. simultaneously; "he took three cookies at a time" [syn: at once, at one time]
Usage examples of "at a time".
After a time Harruel developed the knack of taking the steps two and even three at a time in loping bounds, and the ascent became easier.
But I applied myself to the task and a little at a time I was able to learn their speech.
He seemed willing enough to give instruction, and they spent hours at a time together, Noum om Beng speaking and Hresh listening carefully, trying with more hope than success to seize meanings out of the air.
And did it, Torlyri knew, at a time when she herself was undergoing great stress.