lose an hour of sleep

From the fact that the transitions to and from daylight saving time occur during normal bedtime hours.

lose an hour of sleep (third-person singular simple present loses an hour of sleep, present participle losing an hour of sleep, simple past and past participle lost an hour of sleep)

1. To change the clocks forward by one hour for daylight saving time; the "spring forward" in spring forward, fall back.
   • 2016 March 11, Michelle Hackman, “A dozen states are considering getting rid of daylight saving time. Is that a good thing?”, in Vox‎:

     As Americans brace to lose an hour of sleep this weekend, marking the beginning of daylight saving time, nearly a dozen states are considering abandoning the whole clock-shifting practice altogether.