hair n.
[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!")