Quick Definition
δεῖνα, ὁ, ἡ, τό Adj so and so, such a one
Strong's Definition
probably from the same as 1171 (through the idea of forgetting the name as fearful, i.e. strange); so and so (when the person is not specified)
KJV Usage: such a man
UBS Dictionary of the Greek New Testament
noun, m.
92.19 · Discourse Referentials · Whom or What Spoken or Written About
certain, somebody a reference to an entity which one cannot or does not wish to make explicit (in the NT only a reference to a man) Though in many translations δεῖνα is translated as ‘certain,’ this can give a wrong impression since it would imply that the individual is known to the parties involved or has been identified by the context.
UBS Dictionary of the Greek New Testament © United Bible Societies, licensed CC BY-SA 4.0.
Thayer's Greek Lexicon
δεῖνα, 6, 7, τό ; gen. δεῖνος ; dat. dei; ace. τὸν, τὴν, τὸ δεῖνα (cf. Matthiae § 151), such a one, a certain one, i.e. one whose name 1 cannot call on the instant, or whose name it is of no importance to mention; once in the Scriptures, viz. Mt. xxvi. 18. (Arstph., Dem., al.)
Mounce Concise Greek Dictionary
δεῖνα deina 1x
such a one, a certain one, Mt. 26:18*
Abbott-Smith Greek Lexicon
** δεῖνα, ὁ, ἡ, τό (gen. -νος, dat. -νι, acc. -να),
[in Aq.: Ru 4:1, I Ki 21:2 (3) (Sm. also), IV Ki 6:8 * ;]
such an one, a certain one, whom one cannot or will not name: Mt 26:18.†
Liddell-Scott-Jones — Greek-English Lexicon
δεῖνα (deina) — a certain one. δεῖνα, ὁ, ἡ, τό, genitive δεῖνος, dative δεῖνι, accusative δεῖνα: sometimes indeclinable (see. below): nominative δεῖν, ὁ, [Refs 5th c.BC+]:— such an one, so-and-so, always with Article, ὁ δεῖνα [Refs 5th c.BC+]; τὸ δ., euphemistic for τὸ πέος, [Refs 5th c.BC+] do you eat such a fish? [Refs 4th c.BC+] mine or some other's, [Refs 4th c.BC+]
II. τὸ δ. in Comedy texts as an interjection to express an idea which suddenly strikes one, by the way, mark you, [Refs 5th c.BC+]