when a person is acting shadey...kinda I guess talking smack behind ur back.. then acting like everythings peachy king when youre face to face with them
Based on the word "shyster," meaning "an unethical, unscrupulous practitioner, especially of law." It comes from the German term "scheisser," which literally means "one who defecates."
It can also be used as term to describe a crappy bag of weed or other drugs (shrooms,coke,etc.) that has been pinched or skimmed or sumtin of that sort