Instrument

a device that requires skill for proper use

the means whereby some act is accomplished

a person used by another to gain an end

(law) a document that states some contractual relationship or grants some right

the semantic role of the entity (usually inanimate) that the agent uses to perform an action or start a process

any of various devices or contrivances that can be used to produce musical tones or sounds

equip with instruments for measuring, recording, or controlling

write an instrumental score for

address a legal document to