Alert describes a person or thing extremely aware of what is going on with their surroundings, and is often ready to quickly respond to a possibly dangerous situation.
The definition of ceaseless is continuous.
(Archaic) Wakeful; unsleeping
Being in physical motion:
Marked by an absence of sleep
Having no lid or lids.
Find another word for sleepless. In this page you can discover 15 synonyms, antonyms, idiomatic expressions, and related words for sleepless, like: insomnious, insomnolent, restless, alert, ceaseless, watchful, active, wakeful, insomniac, slumberless and awareness.