Strong's:ἀσπίς a buckler (or round shield); used of a serpent (as coiling itself), probably the "asp"Derivation: of uncertain derivation;KJV Usage: asp.
Thayer:1) an asp, a small and most venomous serpent, the bite of which is fatal unless the bitten part be immediately cut away
ἀσπίς aspis as-pece' Of uncertain derivation; a buckler (or round shield); used of a serpent (as coiling itself), probably the “asp” KJV Usage: asp.