To train for some activity by doing drills on someone or something. (Spelled "practise" in British English.) A noun or pronoun can be used between "practice" and "on" to specify the activity one is training for. The doctor asked if the trainees could practice checking blood pressure and heart rate on me. I want to make sure the sculpture turns out how I want it, so I've been practicing on these concrete blocks before I move on to the marble.