From an unused root meaning the same as shuwph; a kind of serpent (as snapping), probably the cerastes or horned adder -- adder.
see HEBREW shuwph
H8207. shephiphon
שְׁפִיפֹן noun [masculine] horned snake, ᵐ5 κεράστης (Arabic , Frey); — absolute ׳שׁ Genesis 49:17 ("" נָחָשׁ); = cerastes cornutus or Hasselquistii, compare TrNBB 273 PostHast. DB iv. 457 f. McLean-ShipleyEncy. Bib. iv. 4393 Dron the passage — שְׁפוּפָן שְׁפוּפָם, see S. V.