sleepless

[ sleep-lis ]
/ ˈslip lɪs /

adjective

without sleep: a sleepless night.
watchful; alert: sleepless devotion to duty.
always active: the sleepless ocean.

Origin of sleepless

late Middle English word dating back to 1375–1425; see origin at sleep, -less

OTHER WORDS FROM sleepless

sleep·less·ly, adverbsleep·less·ness, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for sleepless

British Dictionary definitions for sleepless

sleepless
/ (ˈsliːplɪs) /

adjective

without sleep or resta sleepless journey
unable to sleep
always watchful or alert
mainly poetic always active or movingthe sleepless tides

Derived forms of sleepless

sleeplessly, adverbsleeplessness, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012