Strong's #2191: echidna (pronounced ekh'-id-nah)

of uncertain origin; an adder or other poisonous snake (literally or figuratively):--viper.

Thayer's Greek Lexicon:

̓́

echidna

1) a viper, offspring of vipers

1a) addressed to cunning, malignant, wicked men

Part of Speech: noun feminine

Relation: of uncertain origin

Citing in TDNT: 2:815, 286

Usage:

This word is used 5 times:

 

Matthew 3:7: "he said unto them, O generation of vipers, who hath warned you to flee"
Matthew 12:34: "O generation of vipers, how can ye, being evil, speak good things?"
Matthew 23:33: "Ye serpents, ye generation of vipers, how can ye escape the damnation"
Luke 3:7: "of him, O generation of vipers, who hath warned you to flee"
Acts 28:3: "the fire, there came a viper out of the heat, and fastened"