Arabic (ميسر) for gambling or broadly any activities or transactions involving a gambling element. In relation to contracts (commutative contracts), maisir arises when one party profits at the expense (loss) of the other, in an uncertain event.

The term is derived from yusr (i.e., ease), where mal (wealth or money) is acquired or wasted easily in gambling (games of chance), where no party has any control over the event on which the final outcomes will be determined and decided.

Maisir (whether on the gain or loss side) is strictly prohibited under shari’ah.