An instrument is a concrete or abstract tool intended for a purpose other than mechanical work, in particular a refined one.
Musical instruments are devices designed to produce music, frequently by plucking or striking a string or bell or drum surface, or by forcing air to resonate (see wind instruments).
...
In the human female, the urethra is about 1-1.5 inches (25-38 mm) long and opens in the vulva between the clitoris and the vaginal opening.
In the human male, the ...