1. (noun)warrant a writ from a court commanding police to perform specified acts
2. (noun)warrant, stock warrant, stock-purchase warrant 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 commonstock at a stated price "as a sweetener they offered warrants along with the fixed-income securities"
3. (noun)sanction, countenance, endorsement, indorsement, warrant, imprimatur formal and explicit approval "a Democrat usually gets the union's endorsement"
4. (noun)guarantee, warrant, warrantee, warranty a written assurance that some product or servicewill be provided or willmeet certain specifications
5. (verb)justify, warrant show to be reasonable or provide adequate ground for "The emergency does not warrant all of us buying guns"; "The end justifies the means"
6. (verb)guarantee, warrant standbehind and guarantee the quality, accuracy, or condition of "The dealer warrants all the cars he sells"; "I warrant this information"