Endorsement (noun)

1. Formal approval or support.
2. A signature on the back of a cheque or bill of exchange authorizing payment to a specified person.

Origin:

Mid 17th century: from french endossement, from endosser 'to endorse'.

Examples:

1. The endorsement of the famous singer brought popularity to the brand.
2. The athlete's endorsement of the sportswear helped it to sell better.
3. The actor's endorsement of the political candidate caused a lot of controversy.
4. The doctor's endorsement of the medicine made it more trustworthy.
5. The endorsement was required for the payment of the cheque.