instrument

The violinist was a master of her instrument.

There the cause of death was soon ascertained ; the victim of this daring outrage had been stabbed to death from ear to ear with a long, sharp instrument, in shape like an antique stiletto, which … was subsequently found under the cushions of the hansom. …

The instrument detected an increase in radioactivity.

Flight within clouds must be made by reference to your instruments.

A bond indenture is the instrument that gives a bond its value.

Or useful serving man and instrument, / To any sovereign state.