Any physical activity required for magic, ranging from simply pointing at the target up to day-long ritual dances. At its simplest, this is just a way of showing the wizard is actually doing stuff. They will point at the target, wave their hand around to move it, and close their fist to crush it. Compare with the Pstandard Psychic Pstance. Moving up a step, some types of spell require precise gestures to work, leading to wizards with very nimble fingers as well as an excuse for them not to wear armor involving the restriction of mobility. The precise gestures have to be memorized as part of the spell.