Lexical Definition

‎ἀθετέω‎ athetéō (ath-et-eh'-o) to reject ^G:V
from a compound of ‎Α‎ (as a negative particle) and a derivative of ‎τίθημι‎

cast off, despise, disannul, frustrate, bring to nought, reject.

• to set aside, i.e. (by implication) to disesteem, neutralize or violate

Abbott-Smith

† ἀθετέω, -ῶ (< τίθημι), [in LXX for seventeen different words, פּשׁע, מרד, בּגד, מעל, etc., often meaning, as I Ki 13:3 (Heb., al.), to revolt; properly, to make ἄθετον, or do away with what has been laid down (v. DCG, i, 453 f.)].

1. to set aside, disregard (in Gramm., to reject as spurious): διαθήκην, Ga 3:16; ἐντολήν, Mk 7:9; νόμον, He 10:28; πίστιν, I Ti 5:12.
2. to nullify, make void: Lk 7:30 (v. Field, Notes, 59), I Co 1:19, Ga 2:21.
3. to reject: Mk 6:26 (Field, op. cit., 30), Lk 10:16, Jo 12:48, I Th 4:8, Ju 8 (for exx. in π., v. MM, VGT, s.v.).†

Abbott-Smith References

Liddell-Scott-Jones

ἀθετέω-έω, ἄθετος

) set at naught a treaty, promise, etc., πίστιν[NT+2nd c.BC+]; deny, disprove, τἀληθές[Refs 5th c.BC+]:—passive, to be struck off a register, [Refs 2nd c.BC+]; to be rejected, of a petition, [Refs 4th c.BC+]:—Astrology texts, cancel, render ineffectual, [Refs 2nd c.AD+]

__2 with dative, refuse one's assent, τοῖς ὑπὸ Τιμαίου εἰρημένοις[Refs 2nd c.BC+]
__3 deal treacherously with, break faith with, τινά[NT+2nd c.BC+]
__II Grammars, reject as spurious, [Refs 1st c.BC+]
__III absolutely, to be unsuitable, unfit, [Refs 4th c.BC+]

_{LSJ Scripture Refs: LXX.1Kgs.2.17 ☩ Gal.3.15 ☩ LXX.Isa.1.2 ☩ Mark.6.26 ☩ LXX.1Kgs.12.19}