To enforce is described as to compel someone to abide by a rule, law or order.(verb)
When the police compel you to obey speed limits or else get a ticket, this is an example of a situation where the police enforce the law.
See enforce in Webster's New World College Dictionary
See enforce in American Heritage Dictionary 4
transitive verb en·forced, en·forc·ing, en·forc·es
Origin: Middle English enforcen
Origin: , from Old French enforcier, to exert force, compel,
Origin: and from enforcir, to strengthen
Origin: : en-, causative pref.; see en-1
Origin: + force, strength; see force.
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