1.NounA 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.; This trombone is very expensive."
2.NounThe common European bittern.
3.NounA kind of extendable support for attaching lighting elements to a set.
4.VerbTo transmit a signal or data back to a central switching point before sending it out to its destination.
5.VerbTo extend and retract (the zoom lens); to use it too enthusiastically.