Quick Definition
a serpent, snake, viper
Strong's Definition
an adder or other poisonous snake (literally or figuratively)
Derivation: of uncertain origin;
KJV Usage: viper
Thayer's Greek Lexicon
ἔχιδνα, ἐχιδνης, ἡ, a viper: Act_28:3 (Hesiod, Herodotus, Tragg., Aristophanes, Plato, others); γεννήματα ἐχιδνῶν offspring of vipers (anguigenae, Ovid, metam. 3,531), addressed to cunning, malignant, wicked men: Mat_3:7; Mat_12:34; Mat_23:33; Luk_3:7.
Mounce Concise Greek Dictionary
ἔχιδνα echidna 5x
a viper, poisonous serpent, Act_28:3 ;
used also fig. of persons, Mat_3:7 ; Mat_12:34 ; Mat_23:33 ; Luk_3:7
Abbott-Smith Greek Lexicon
** ἔχιδνα , -ης , ἡ ,
[in OT ( Aq .), Isa_59:5 * ;]
a viper: Act_28:3 ; metaph ., γεννήματα ἐχιδνῶν , Mat_3:7 ; Mat_12:34 ; Mat_23:33 , Luk_3:7 .†
Moulton & Milligan — Vocabulary of the Greek NT
ἔχιδνα [page 270]
Ramsay ( Luke , p. 63 ff.) has shown that by the ἔχιδνα of Act_28:3 we are probably to understand a constrictor snake, closely resembling a viper, without poison-fangs, which fixes its teeth firmly into the human skin so as to hang on, without, however, doing any real injury to the skin. The verb καθῆψεν in the sense of fastened upon rather than bit ( momordit, Blass) is therefore correctly applied to it, as against Harnack Lukas der Arzt , p. 123 f. (E. Tr., p. 177 f.). On γεννήματα ἐχιδνῶν as equivalent to the simple ἔχιδναι in Mat_3:7 see McNeile ad l. , following Nestle in ZNTW xiv. p. 267 f.
Liddell-Scott — Intermediate Greek Lexicon
ἔχιδνα ἔχιδνα, ἡ, [Etym: ἔχις] "an adder, viper", Hdt. , Trag. , etc.; metaph. of a treacherous wife or friend, Aesch. , Soph.
STEPBible — Tyndale Abridged Greek Lexicon
ἔχιδνα, -ης, ἡ
[in OT (Aq.), Isa.59:5 * ;]
a viper: Act.28:3; metaphorically, γεννήματα ἐχιδνῶν, Mat.3:7 12:34 23:33, Luk.3:7.†
(AS)