Sorry, Loctite is a threadlocker. It comes in different strengths (blue or medium strength is quite common) in a little tube in a blister pack available at auto parts stores. It'll prevent the screw (or shift knob in this case) from loosening or backing out.
Whenever you have a screw or bolt or nut that keeps loosening due to vibration, put a little Loctite on it and you'll be all set.