The Chinese term for "security" (as in a financial instrument), 证券 (zhèngquàn), is a logical compound word formed by combining two characters: 证 (zhèng), meaning "proof", "certificate", or "to testify", and 券 (quàn), which historically means "ticket", "voucher", or "deed". Together, they create the concept of a "proof ticket" or a "certificated deed", perfectly capturing the essence of a tradable financial instrument that represents a formal, legal claim to ownership (like a stock) or debt (like a bond). The term thus semantically denotes a document that certifies a financial right or entitlement.