The term 'FETTER' is a six-letter crossword solution for the terms 'CHAIN' and 'SHACKLE'. FETTER is a noun that refers to a CHAIN or SHACKLE used to restrain someone or something, usually as a form of punishment. It can also refer to any kind of restraint or limitation on freedom. Historically, fetters were used to restrain prisoners, but they are now more commonly used in figurative senses to refer to any kind of restriction or limitation.