dead sleep

listen to the pronunciation of dead sleep
الإنجليزية - التركية
derin uyku
الإنجليزية - الإنجليزية
The first sleep of the night in a biphasic sleep pattern

Until the close of the early modern era, Western Europeans on most evenings experienced two major intervals of sleep bridged by up to an hour or more of quiet wakefulness. The initial interval of slumber was usually referred to as “first sleep,” or, less often, “first nap” or “dead sleep.”.

{i} sleep, slumber
dead sleep