serving or tending to deter.

something that deters

a deterrent to crime.

military strength or an ability to defend a country or retaliate strongly enough to deter an enemy from attacking.

noun

catalyst , encouragement , incentive

noun

bridle , check , curb , defense , determent , discouragement , disincentive , hindrance , leash , obstacle , preventative , preventive , rein , shackle , block , hurdle , impediment , restraint

adjective

preclusive , preventative