The word "diccolo" originates from a short, woodwindinstrument named piccolo. Diccolo, as the name suggests, is a small penis and is used mostly to mock a tiny male general's size.
Sarah: "So what instrument do you play in band?"
Jake: "(As an intent for a laughter) My meatflute.
Rob: "you mean a diccolo?"
Someone who studies and specializes in the male organ.
A doctor that checks up on the testicles and has to look at someone's dick for eg diseases (STD's), or misshapes.