When you ejaculate on someone's face and throw flour on it right after.

Catching someone in the act of ghostin'.

One of the best movies of the 1980's, and later went on to spawn an immensely popular cartoon series (some claimed it equal in popularity to the later Teenage Mutant Ninja Turtles in the early 90's), and later an equally entertaining sequel. Then, in the mid-90's, a spin-off cartoon series was released in hopes of reviving the franchise (entitled "Extreme Ghostbusters"), but was nowhere near as good as the original.

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Group of special agents who specialize in the capture and apprehension of ghosts, demons, cretins, evil spirits, etc. Ghostbusters should be called whenever paranormal activities are suspected, including when there is something strange in the neighborhood or an invisible man sleeping in your bed.

The manner in which a male's stream of urine divides into 2 or more incongruous streams, when urinating directly after sex. This phenomena of 2 or more streams which don't cross is highly reminiscent of the laser's emitted by the Ghostbusters guns.

When a party is broken up by the host(s) under the false pretense that the cops are outside, when in fact, upon leaving, you discover there are no police at all.

Who you're gonna call, should there be something strange in your neighbourhood.

Private paranormal investigation and elimination company founded in New York City in 1984, by discredited former Columbia scientists Dr’s Peter Venkman, Raymond Stantz and Egon Spengler. Ghostbusters employees typically charged between 4000 and 5000 dollars per ghost removed, which meant the service was a slight premium.
The Ghostbuster’s ghost elimination policies came in for much debate criticism, some speculated whether they were the source of the sudden unexplained increases in spectral activity in the tri-state area. Others including the EPA, were concerned about their use of unliscened nuclear accelerators in their work and the waste chemicals in their basement. This came to a head with the EPA shutting down their ghost storage facility which had the equivalent effect of dropping a bomb on the city. The Ghostbusters (now including Winston Zeddemore) were arrested and eventually cleared of all charges and proceeded to stop an invading god-like being called Gozer The Gozarian which took the form of a hundred foot marshmallow gay sailor on shore leave. By crossing their nuclear accelerator streams they managed to destroy the marshmellow sailor, create a marshmallow rain storm and blow the top 15 floors off of 55 Central Park West.
Despite saving the world once more Ghostbusters Inc shut down for good in 1991 amidst huge debts and lack of business.