Laya is the pace at which the matras of a taal go by. Hindustani music recognises three broad speeds: vilambit (slow), madhya (medium) and drut (fast). A full performance often travels through them, beginning slow and accelerating.
But laya is more than a setting — it is something a musician actively shapes. Playing with laya (subdividing it, doubling it, pulling against it) is layakari, one of the highest rhythmic arts.
A steady internal sense of laya is what lets a soloist wander melodically for many beats and still arrive exactly on the sam.