The verb endorse means to say publicly that you support or approve someone or something.

Synonyms are advocate, authorize, affirm, or approve.

The word origins from Old French endosser (12th century), literally “to put on the back”, from en– meaning “put on” plus dos meaning “back”. It also sources from medieval Latin (late 15th century) indorsare, from Latin in- meaning “in, on” plus dorsum meaning “back”.

People are eager to copy the products that celebrities endorse.

The king endorsed the document with a seal.

I certainly don’t endorse her views.