1. a writ from a court commanding police to perform specified acts
2. a type of security issued by a corporation (usually together with a bond or preferred stock) that gives the holder the right to purchase a certain amount of common stock at a stated price;
"as a sweetener they offered warrants along with the fixed-income securities"
3. formal and explicit approval;
"a Democrat usually gets the union's endorsement"
4. a written assurance that some product or service will be provided or will meet certain specifications