A regulation requiring people to remain indoors between specified hours, or a time by which someone must return home.
From Old French 'covrefeu,' literally meaning 'cover fire' ('couvrir' = to cover + 'feu' = fire). In medieval times, this was the evening bell that signaled when people had to extinguish or cover their fires to prevent nighttime blazes that could destroy entire wooden towns. The bell became associated with the time everyone had to be inside and settled for the night. What started as a fire safety measure became a general evening restriction.
Medieval fire safety gave us the modern teenager's nemesis! 'Curfew' literally meant 'cover your fire' — towns rang bells each evening to remind everyone to bank their hearth fires so they wouldn't burn down the neighborhood overnight. Since everyone had to be home to tend their fires anyway, it naturally became the time when people stayed indoors. So your parents' curfew rules trace back to medieval fire prevention.
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