Real Dictionary

wind down
phrasal verb: If someone winds down a business or activity, or if it winds down, they gradually reduce the amount of work that is done or the number of people that are involved, usually before closing or stopping it completely.
phrasal verb: If you wind down, you relax after doing something that has made you feel tired or tense.
phrasal verb: When you wind down something such as the window of a car, you make it move downwards by turning a handle.

wind down in American English
to bring or come to an end; conclude
to lessen in intensity so as to bring or come to a gradual end

wind down in British English
to lower or move down by cranking

wind-down in American English
noun: an act or instance of winding down, as in intensity