Means of control is a term used to describe the various methods used to regulate or influence behavior. The crossword solutions for this term are REIN (4 letters), REINS (5 letters), and BUTTON (6 letters). REIN is a strap or rope used to guide or restrain an animal, such as a horse. REINS are a set of REINS used to control a horse. BUTTON is a small disk or knob used to fasten clothing or to operate a device, such as a doorbell.