Definitions of endorse
to give your approval or support to someone or something, especially in public; to recommend a product in an advertisement
Every candidate must be endorsed by at least 500 elected officials to stand.
to sign a cheque, bill of exchange or other negotiable (=transferable) instrument to make it payable to another person or cashable by any person; to write the signature itself
Jones insisted that he had 'never signed, endorsed or approved' the cheque.