Quick Definition
θυρεός, οῦ, ὁ n.m. a large shield
Strong's Definition
from 2374; a large shield (as door-shaped)
KJV Usage: shield
UBS Dictionary of the Greek New Testament
noun, m. | -οῦ | θύρα
6.40 · Artifacts · Weapons and Armor
shield a long, oblong shield; used to protect the entire body in battle; made of wood, metal, leather stretched over wood, or plaited strips of wood or reeds In some languages ‘shield’ is described as ‘protection one carries when one fights’ or ‘protection carried to prevent blows from the enemy.’ The phrase ἀναλαβόντες τὸν θυρεὸν τῆς πίστεως may thus be rendered as ‘take hold of faith as a protection against the enemy’ or ‘regard your faith as a protection to prevent the attacks of the enemy.’
UBS Dictionary of the Greek New Testament © United Bible Societies, licensed CC BY-SA 4.0.
Thayer's Greek Lexicon
θυρεός, -οὔ, 6, (fr. θύρα, because shaped like a door [ef. W. 287), α shield (Lat. scutwn); it was large, oblong, and four-cornered: τὸν 0. τῆς πίστεως, i. 4. THY πίστιν ὡς θυρεόν, Eph. vi. 16. It differs from ἀσπίς (Lat. clipeus), which was smaller and circular. [Polyb., Dion. Hal., Plut., al.]
Mounce Concise Greek Dictionary
θυρεός thureos 1x
a stone or other material employed to close a doorway; later, a large oblong shield, Eph. 6:16*
Abbott-Smith Greek Lexicon
θυρεός, -οῦ, ὁ
(< θύρα), [in LXX for מָגֵן, צִנָּה;]
in Hom., a door-stone.
In late Gk. (Polyb., Plut.), the scutum, a large oblong shield: θ. τ. πίστεως, Eph 6:16 (cf. Wi 5:20, where ὁσιότης is likened to the ἀσπίς, the clypeus or small round shield of the light-armed soldier).†
Moulton & Milligan — Vocabulary of the Greek NT
θυρεός. For the late usage of this word for the long oblong shield of Roman equipment (cf. Polyb. vi. 23. 2), as in Eph 61%, see PSI IV. 428% (iii/z.c.) ὅπλα ἀσπὶς φαρέτρα θυρεός
Liddell-Scott-Jones — Greek-English Lexicon
θυρεός (thureos) — long shield. θῠρεός, ὁ, (θύρα) stone put against a door to keep it shut, [Refs 8th c.BC+]
II. oblong shield (shaped like a door), [Refs 3rd c.BC+], Inscription cited in [Refs 3rd c.BC+]; hence, of the Roman scutum (opposed to ἀσπίς,= clipeus), [NT+2nd c.BC+]
III. disk forming part of καθετήρ, [Refs 3rd c.BC+]
IV. in Mathematics texts, oval, [Refs 5th c.AD+]