This is a term derived from the Skittles catchline "Taste the rainbow". To shoot the rainbow you must have Skittles-infused vodka and you must take consecutive shots of each of the 5 flavors (normally Skittles vodka requires separation of the different colors, otherwise you just get disgustingly sweet vodka). Some people use various color orders when shooting the rainbow but the most common order goes red (strawberry), orange (WTF do you think the flavor is if the thing's color is "orange"?), yellow (lemon), green (lime) and lastly purple (grape). Sometimes red and yellow are switched so that the order goes by color depth or some people just by their own taste.

(noun) A successful type of theft which results in an acceptable, impressive and rewarding payday for the protagonist.