The act of casting a spell. Often comes with visible manifestations of magic, such as glowing particles, magical auras, runic magic circles, and/or a ball of energy (e.g. fireball) being gathered and shaped in the caster's hand or a wielded tool.
Chanting spell incantations may also sometimes count, even if there is no overt visible manifestation of magic. This depends on context: most fantasy examples count, while people doing the same in a magic-less setting generally do not. Basically it has to be an actual spell (explicitly or implied in context) to qualify.
