(Ps. 140:3; Rom. 3:13, “asp”) is the rendering of, (1.) Akshub (“coiling” or “lying in wait”), properly an asp or viper, found only in this passage. (2.) Pethen (“twisting”), a viper or venomous serpent identified with the cobra (Naja haje) (Ps. 58:4; 91:13); elsewhere “asp.” (3.) Tziphoni (“hissing”) (Prov. 23:32); elsewhere rendered “cockatrice,” Isa. 11:8; 14:29; 59:5; Jer. 8:17, as it is here in the margin of the Authorized Version. The Revised Version has “basilisk.” This may have been the yellow viper, the Daboia xanthina, the largest and most dangerous of the vipers of Palestine. (4.) Shephiphon (“creeping”), occurring only in Gen. 49:17, the small speckled venomous snake, the “horned snake,” or cerastes. Dan is compared to this serpent, which springs from its hiding-place on the passer-by.
Adder
Only five verses speak of the adder, and none of them is kind to it. Jacob blesses Dan as “an adder in the path, that biteth the horse heels”; the psalmist says the wicked are like “the deaf adder that stoppeth her ear” and have “adders’ poison” under their lips. Proverbs 23:32 says wine “stingeth like an adder.” Then comes a promise in Psalm 91:13, “Thou shalt tread upon the lion and adder,” a picture of safety in the middle of danger. Whether it is a bite, a poisoned word or a rescue, the snake is small and the harm is real.
5 verses
Genesis
Dan shall be a serpent by the way, an adder in the path, that biteth the horse heels, so that his rider shall fall backward.
Psalms
Their poison is like the poison of a serpent: they are like the deaf adder that stoppeth her ear;
Thou shalt tread upon the lion and adder: the young lion and the dragon shalt thou trample under feet.
They have sharpened their tongues like a serpent; adders' poison is under their lips. Selah.
Proverbs
At the last it biteth like a serpent, and stingeth like an adder.
From Easton's Bible Dictionary
Matthew George Easton, 1897