Word family noun sleep sleeper sleepiness sleeplessness adjective asleep sleepless sleepy verb sleep adverb sleepily sleeplessly
From Longman Dictionary of Contemporary Englishsleeplesssleep‧less /ˈsliːpləs/ adjective 1 → a sleepless night2 unable to sleep She lay sleepless for hours, worrying. —sleeplessly adverb —sleeplessness noun [uncountable]Examples from the Corpus
sleepless• The four travellers passed a sleepless night, each thinking of the gift Oz had promised to bestow on him.• Sheila spent many sleepless nights figuring out how to deliver for her first major customer.• Doing anything more led to agony, sleepless nights, months of drinking and moping and boring her closest friends to death.• Ask yourself: what will be causing them their sleepless nights ten years from now?• There are many life situations and emotional circumstances that can cause sleepless nights.• the sleepless parents of newborn babies• They brought him back to her six days later, ending one vigil of sleepless prayers and beginning another.• Having lain sleepless until the early hours, it was almost eleven-thirty the next day before Luce surfaced. 