sack rat(redirected from sack rats)
slang Someone who spends an inordinate amount of time sleeping or lounging in bed. ("Sack" is a colloquial term for "bed.") I used to be such a sack rat when I was in college, spending entire days in bed. Now that I have kids, I'm lucky if I can get eight uninterrupted hours in bed each night.
n. someone who spends a lot of time in bed; someone who does not ever seem to get enough sleep. Tom is such a sack rat. He can’t seem to get enough sleep.