Quick Definition
νῆστις, ιος, ὁ, ἡ Adj fasting, without food
Strong's Definition
from the inseparable negative particle ne- (not) and 2068; not eating, i.e. abstinent from food (religiously)
KJV Usage: fasting
UBS Dictionary of the Greek New Testament
adjc. | -ιος, -ιδος · acc.pl. νήστεις | νηστεύω
23.31 · Physiological Processes and States · Eat, Drink
to be quite hungry, considerable hunger, lack of food the state of being very hungry, presumably for a considerable period of time and as the result of necessity rather than choice (compare νηστεία[a] ‘fasting,’ 53.65) Terms referring to hunger often distinguish varying degrees of hunger and whether the hunger is by necessity or by choice.
UBS Dictionary of the Greek New Testament © United Bible Societies, licensed CC BY-SA 4.0.
Thayer's Greek Lexicon
νῆστις, acc. plur. νήστεις and (so Tdf. [cf. Proleg. p. 1187) νήστις (see Lob. ad Phryn. p. 326; Fritzsche, Com. on Mk. p. 796 sq.; ef. [ WH. App. p. 157°]; B. 26 (23)), 6, ἡ, (ἔτ. νη and ἐσθίω, see νήπιος), fasting, not having eaten: Mt. xv. 32; Mk. viii. 3. (Hom., Aeschyl., Hippocr., Arstph., al.)
Mounce Concise Greek Dictionary
νῆστις nēstis 2x
can also be masc. with a gen. in ιδος (n-3c[2]), fasting, hungry, Mt. 15:32; Mk. 8:3*
Abbott-Smith Greek Lexicon
νῆστις, -ιος, ὁ, ἡ
(< νη-, neg. prefix, + ἐσθίω),in cl., chiefly poët., [in LXX: Da LXX 6:18 (19) (טְוָת)*;]
not eating, fasting: Mt 15:32, Mk 8:3.†
Liddell-Scott-Jones — Greek-English Lexicon
νῆστις (nēstis) — fasting. νῆστις, genitive ιος or ιδος, ὁ and ἡ (see. below); also dative νήστει [Refs 5th c.BC+]: (νη-, ἔδω):—not eating, fasting, of persons, ἀνώγοιμι πτολεμίζειν υἷας Ἀχαιῶν νήστιας, ἀκμήνους [NT+8th c.BC+] over the hungry sand, [Refs 4th c.BC+]
2. with an abstract substantive, frequently in [Refs 4th c.BC+]famine, [Refs]; νήστισιν αἰκίαις the pains of hunger, Pr.[Refs]; νήστιδες δύαι [Refs]; also νῆστις ὀσμή the bad breath of one fasting, [Refs 5th c.BC+]
3. active, causing hunger, starving, πνοαὶ νήστιδες [Refs 4th c.BC+]
II. as substantive, νῆστις, ἡ, accusative νῆστιν [Refs 5th c.BC+]
II.1. the intestinum jejunum, from its always being found empty, [Refs 5th c.BC+]
II.2. ν. κεστρεύς, fish so called because its stomach was always found empty, [Refs 5th c.BC+]: hence in Comedy texts, of 'empty bellies', ἐγὼ δὲ κεστρεὺς νῆστις οἴκαδ᾽ ἀποτρέχω [Refs 2nd c.AD+]
II.3. Νῆστις, ἡ, ={ὕδωρ}, [Refs 5th c.BC+]