trombone

A musical instrument in the brass family, having a cylindrical bore, and usually a sliding tube (but sometimes piston valves, and rarely both). Most often refers to the tenor trombone, which is the most common type of trombone and has a fundamental tone of B♭ˌ (contra B♭).

“Jim plays the trombone very well.”

The common European bittern.

To transmit a signal or data back to a central switching point before sending it out to its destination.

To extend and retract (the zoom lens); to use it too enthusiastically.