1) to nod in sleep, to sleep
1a) to be overcome or oppressed with sleep
1b) to fall asleep, drop off to sleep
2) to be negligent, careless
2a) of a thing, i.e. to linger, delay
Part of Speech: verb
From a presumed derivative of G3506; to nod, that is, (by implication) to fall asleep; figuratively to delay: - slumber.
These two sites give similar information, with the definition from several dictionaries and statistics on the use of the word.
Perseus Digital Library
University of Chicago's Logion lexicon
Thayer's dictionary plus other information.
From this site's dictionary (in Italian)
Click on the first column to search for that word as a form of the root νυστάζω; click on the second column to search for that grammatical form of the root νυστάζω; click on the third column to search for that word and grammatical form; click on the total to search for the root νυστάζω.