1. the act of endorsing

e.g. a star athlete can make a lot of money from endorsements

Synonym: endorsement

2. a signature that validates something

e.g. the cashier would not cash the check without an endorsement

Synonym: endorsement

3. formal and explicit approval

e.g. a Democrat usually gets the union's endorsement

Synonym: sanctioncountenanceendorsementwarrantimprimatur

4. a speech seconding a motion

e.g. do I hear a second?

Synonym: secondsecondmentendorsement

5. a promotional statement (as found on the dust jackets of books)

e.g. the author got all his friends to write blurbs for his book

Synonym: endorsementblurb