Quick Definition
νυστάζω v. I nod in sleep, am drowsy, slumber
Strong's Definition
from a presumed derivative of 3506; to nod, i.e. (by implication) to fall asleep; figuratively, to delay
KJV Usage: slumber
UBS Dictionary of the Greek New Testament
verb
23.67 · Physiological Processes and States · Sleep, Waking
to grow drowsy the process of becoming sleepy ‘To grow drowsy’ may be rendered in some languages as ‘to begin to nod’ or ‘their heads fell’ or ‘their eyes gradually closed.’
In 2PE 2:3 νυστάζω occurs in a highly figurative context: καὶ ἡ ἀπώλεια αὐτῶν οὐ νυστάζει, literally ‘and their destruction is not drowsy,’ meaning either ‘their destruction is imminent’ or ‘their Destroyer has been wide awake’ (see Today’s English Version).
UBS Dictionary of the Greek New Testament © United Bible Societies, licensed CC BY-SA 4.0.
Thayer's Greek Lexicon
νυστάζω : 1 aor. ἐνύσταξα ; (NYQ, cf. νεύω, νευστάζω); Sept. for 033; 1. prop. to nod in sleep, to sleep, (Hippocr., Arstph., Xen., Plato, al:); to be overcome or oppressed with sleep; to fall asleep, drop off to sleep, [ (cf. Wiclif) to nap it]: Mt. xxv. 5; Sept. for 07373, Ps. Ixxv. (Ixxvi.) 7. 2. like the Lat. dormito [ef. our to be napping |, trop. i.q. to be negligent, careless, (Plat., Plut., al.): of a thing i. q. fo linger, delay, 2 Pet. ii. 3.
Mounce Concise Greek Dictionary
νυστάζω nystazō 2x
to nod; to nod in sleep; to sink into a sleep, Mt. 25:5; to slumber in inactivity, 2 Pet. 2:3*
Abbott-Smith Greek Lexicon
νυστάζω
(cf. νεύω), [in LXX for נוּם, etc;]
to nod in sleep, fall asleep: Mt 25:5. Metaph., of negligence or delay, ἡ ἀπώλεια αὐτῶν οὐ νυστάζει (cf. Ps 120 (121):4, Is 5:27): II Pe 2:3.†
Liddell-Scott-Jones — Greek-English Lexicon
νυστάζω (nustazō) — to doze. νυστ-άζω, future -άξω [LXX]: aorist ἐνύσταξα [LXX+4th c.BC+]:— mostly present, to be half asleep, doze, νυστάζοντα οὐδένα ἂν ἴδοις [Refs 5th c.BC+]; οὐχὶ νυστάζειν ἔτι ὥρα ’στίν [Refs 5th c.BC+]; ἔν τινι in a thing, [Refs 1st c.AD+]
2. hang the head, ἐδάκρυσεν καὶ ἐνύστασε [Refs].with (Cf. Lithuanian snústi (stem snúd-) 'grow drowsy'.)