A pledge is a serious promise to do something or support something. When you make a pledge, you're making a firm commitment you intend to keep.

Students across America recite the Pledge of Allegiance at school, promising loyalty to their country. When someone pledges to donate money to charity, they're making a binding commitment to give that amount. Girl Scouts and Boy Scouts make pledges to follow the values of their organizations. Before taking office, the President of the United States takes a pledge called the oath of office.

The word carries weight because a pledge is supposed to be taken seriously. When you pledge your word or pledge your honor, you're putting your integrity on the line.

As a verb, to pledge means to make such a promise: “She pledged to practice piano every day” or “He pledged allegiance to the country.” The word suggests true commitment to follow through, even when it gets difficult.