1. Act of squatting behind a male and performing annilingus while also performing hand stimulation on same male's penis.

2. a brass wind instrument operated by moving a slide to create differences in pitch that has iron oxide on its surface usually from prolonged exposure to moisture.

When a chick gives a guy a reach-around while pressing her lips to the asscrack of a guy as he farts, thus making it seem and sound like she is playing a rusty trombone. Makes me want to join the marching band.

When a girl blows on your ass as she cradles your dick

Rusty Trompone: The sexual act where one partner gives a rim job while also giving their lucky partner the ol' reach around.

when a female kneels behind a stanind man , licks his arsehole, reaches around and tugs the dick like a trumpet

the act of sucking ass while giving the old grab and yanky yanky

The act of performing anal cunnilingus while reaching up above the testicles to manually administer quick up and down motions to the penile shaft; resulting in a violent yet pleasant explosion. It is then customary for the female to then give a quick blow into the anus for good luck, the lips blowing into the anus sounds very similar to a trombones sweet melody. This was introduced to the Americas in the late 50's.