Pre-ejaculate (also known as pre-ejaculatory fluid, preseminal fluid, or Cowper's fluid, and colloquially as pre-cum) is the clear, colorless, viscous fluid that emits from the urethra of a man's penis when he is sexually aroused. It is similar in composition to semen, but has some significant chemical differences. The presence of sperm in the fluid is very unlikely. Pre-ejaculate is believed to function as a lubricant and an acid neutralizer. The amount of pre-ejaculate emitted varies widely between individual men. Slang terms for pre-ejaculate include pre-come, pre-cum, dog water, and speed drop. Whatever you want to call it, I love it!