1. Operating at a rate determined by the system rather than at a regular rate of chronological time; without a fixed time pattern: "The injection of the new medication was supposed to correct the asychronism of the nerve impulses."
2. Describing the relationship of two or more systems that run at their own rates and interact at unpredictable times: "Despite practicing for weeks, the gymnast's jumping jacks appeared to be asynchronisms or uncoordinated."

Not coinciding in time; not corresponding in time.