noun
Date: 14th century
the action of obligating oneself to a course of action (as by a promise or vow),
2. something (as a formal contract, a promise, or the demands of conscience or custom) that obligates one to a course of action, a debt security (as a mortgage or corporate bond), a commitment (as by a government) to pay a particular sum of money,
3. a condition or feeling of being obligated, a debt of gratitude, something one is bound to do ; duty , responsibility