[back-formation from hairy] The complications that make something hairy. "Decoding TECO commands requires a certain amount of hair." Often seen in the phrase "infinite hair", which connotes extreme complexity. Also in "hairiferoUS" (tending to promote hair growth): "GNUMACS elisp encourages lUSers to write complex editing modes." "Yeah, it' s pretty hairiferoUS all right." (Or jUSt: "Hair squared!")