S: (n) restraint, constraint (a device that retards something's motion) "the car did not have proper restraints fitted"
S: (n) air bag (a safety restraint in an automobile; the bag inflates on collision and prevents the driver or passenger from being thrown forward)
S: (n) airbrake, dive brake (a small parachute or articulated flap to reduce the speed of an aircraft)
S: (n) arrester, arrester hook (a restraint that slows airplanes as they land on the flight deck of an aircraft carrier)
S: (n) band (a restraint put around something to hold it together)
S: (n) brake (a restraint used to slow or stop a vehicle)
S: (n) brake (anything that slows or hinders a process) "she wan not ready to put the brakes on her life with a marriage"; "new legislation will put the brakes on spending"
S: (n) brake pad (one of the pads that apply friction to both sides of the brake disk)
S: (n) brake shoe, shoe, skid (a restraint provided when the brake linings are moved hydraulically against the brake drum to retard the wheel's rotation)
S: (n) catch, stop (a restraint that checks the motion of something) "he used a book as a stop to hold the door open"
S: (n) sea anchor, drogue (restraint consisting of a canvas covered frame that floats behind a vessel; prevents drifting or maintains the heading into a wind)
S: (n) shackle, bond, hamper, trammel (a restraint that confines or restricts freedom (especially something used to tie down or restrain a prisoner))
S: (n) trammel (a restraint that is used to teach a horse to amble)