Urethral sounds are medical instruments used to increase the inner diameter of the urethra. The goal of their use is either, when used medically, to correct an abnormally narrow urethra; or, when used as a sex toy, to produce sexual pleasure per se or to enable the insertion of other objects into the urethra for sexual pleasure. Sounds are long, metallic rods with a range of girths - the point being to start with a small girth and work up to larger girths.

The urethra is exposed to far more nerves per unit area than the outer penis - hence some men find the sensation of urthral stimulation far more pleasurable than more traditional sexual activity - this is especially true among those with certain forms of penile damage. A urethral sound may be connected to special electrical device for use as an electrode in erotic electrostimulation.