instrument

noun | in·stru·ment

1. : a means or implement by which something is achieved, performed, or furthered an instrument of crime

2. : a document (as a deed, will, bond, note, certificate of deposit, insurance policy, warrant, or writ) evidencing rights or duties especially of one party to another under the law a person is not liable on an instrument unless the person signed the instrument —Uniform Commercial Code an indictment is a form of charging instrument specifically : negotiable instrument : negotiable instrument