Strong's Greek #3155 - μάτην matén (in vain)

in vain.

Accusative case of a derivative of the base of massaomai (through the idea of tentative manipulation, i.e. Unsuccessful search, or else of punishment); folly, i.e. (adverbially) to no purpose -- in vain.

see GREEK massaomai

Strong's 3155: μάτην

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: Matthew 15:9 and Mark 7:7, after Isaiah 29:13 the Sept..

Strong's Greek: 3155. μάτην (matén) — 2 Occurrences

Matthew 15:9 - Adv
GRK: μάτην δὲ σέβονταί
NAS: BUT IN VAIN DO THEY WORSHIP
KJV: But in vain they do worship me,
INT: in vain moreover they worship

Mark 7:7 - Adv
GRK: μάτην δὲ σέβονταί
NAS: BUT IN VAIN DO THEY WORSHIP
KJV: Howbeit in vain do they worship me,
INT: in vain moreover they worship