There are several synonyms for the term "share certificate," which refers to a physical document that certifies a person's ownership of shares in a company. Some of these synonyms include stock certificate, equity certificate, share document, investment certificate, and security certificate. These terms all refer to the same type of document, which typically includes information such as the owner's name, the number of shares owned, and details about the company's stock. Share certificates have traditionally been the primary way that investors prove their ownership of shares, but with the rise of digital trading platforms, some companies are starting to move toward electronic certificates.