Quick Definition
in vain
Strong's Definition
folly, i.e. (adverbially) to no purpose
Derivation: accusative case of a derivative of the base of G3145 (μασσάομαι) (through the idea of tentative manipulation, i.e. unsuccessful search, or else of punishment);
KJV Usage: in vain
Thayer's Greek Lexicon
μάτην (accusative (cf. Winers Grammar, 230 (216); Buttmann, § 131, 12) of μάτη, equivalent to ματία, a futile attempt, folly, fault), adverb, from Pindar, Aeschylus down, in vain, fruitlessly: Mat_15:9 and Mar_7:7, after Isa_29:13 the Sept..
Mounce Concise Greek Dictionary
μάτην matēn 2x
in vain, fruitlessly, without profit, Mat_15:9 ; Mar_7:7
Abbott-Smith Greek Lexicon
μάτην
( prop . acc of μάτη , a fault, folly), adv. ,
[in LXX for H1891 , H7723 , etc.;]
in vain, to no purpose: Mat_15:9 , Mar_7:7 ( LXX ).†
Moulton & Milligan — Vocabulary of the Greek NT
μάτην [page 391]
For this adverb, in vain, to no purpose, cf. the illiterate P Amh II. 130 .5 (A.D. 70) ἐξλῆθα ( l. ἐξῆλθα ?) εὑρὼν ἓκξ (ἓξ ) ἑπτὰ μάτιαν πολούτων ( l. μάτην πωλοῦντας ), I came away after finding six or seven offering in vain to sell (some barley) (Edd.), and P Oxy XII. 1417 .22 (early iv/A.D.) μάτη̣ν̣ οὖν θέλω διὰ σοῦ τοῦ στρατηγοῦ , and for the interesting phrase ἐπὶ μάτην cf. ib. III. 530 .8 (ii/A.D.) ἐπὶ μάτ̣η̣[ν ] δὲ τῶι τοῦ Παυσιρίωνος τοσοῦτον χρόνον προσκαπτερ [ῶ , and that I have so long been engaged with Pausirion s business to no purpose (Edd.). Εἰς μάτην is similarly used by Lucian ( Trag. 28, 241).
Liddell-Scott — Intermediate Greek Lexicon
μάτην [Etym: from μά^τη] "in vain, idly, fruitlessly", Lat. frustra, Hhymn. , Pind. , attic; μ. ὁ μόχθος "in vain" the labour, Aesch. ; with a Noun, τὸ μ. ἄχθος the "fruitless" burthen, id=Aesch. "at random, without reason", Lat. temere, Theogn. , Hdt. , attic; ὁ νοσῶν μ., of a madman, Soph. "idly, falsely", Lat. falso, id=Soph. ; μ. βέβακεν, of a dream, Aesch.
STEPBible — Tyndale Abridged Greek Lexicon
μάτην
(prop. accusative of μάτη, a fault, folly), adv., [in LXX for הָבַל, שָׁוְא, etc. ;]
in vain, to no purpose: Mat.15:9, Mrk.7:7" (LXX) .†
(AS)