asp vs viper

asp and viper both are nouns.

Word	Noun	Adjective	Verb	Adverb
asp	Yes	No	No	No
viper	Yes	No	No	No

As nouns, viper is a hypernym of asp; that is, viper is a word with a broader meaning than asp:

asp: of southern Europe; similar to but smaller than the adder
viper: venomous Old World snakes characterized by hollow venom-conducting fangs in the upper jaw

asp (noun)	viper (noun)
of southern Europe; similar to but smaller than the adder	venomous Old World snakes characterized by hollow venom-conducting fangs in the upper jaw
cobra used by the Pharaohs as a symbol of their power over life and death