Definition: Sure, here's how I'd explain "keisters":

Slang or Profane Word: KEISTERS: - A term that is used to describe a small package of cigarettes. - It comes from the French word for "chaise," which means "chair" in English. PROFANE EXAMPLE SENTENCE: "I'm gonna give you a keister to eat while I'm at it." In this example, "keister" is a profanity-like term used to describe a small packet of cigarettes, and it's a playful way of saying "eat me." This sentence is edgy and unsettling because it uses an unexpected word with a negative connotation.