Snake - cobra - to scorn it would be mad (3,11)
I believe the answer is:
boa constrictor
'snake cobra' is the definition.
'boa constrictor' can be an answer for 'snake' (I have seen 'Large snake ' mean 'boa constrictor' so perhaps 'snake' could also mean 'boa constrictor'). I'm not certain of the 'cobra' bit.
'to scorn it would be mad' is the wordplay.
I cannot quite understand how this works, but
'to' is found in the answer.
'it' could be 't' (abbreviation. e.g. in 'tis) and 't' is found within the answer.
an anagram of 'scorn' is 'consr' which is within the remaining letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for boa constrictor that I've seen before include "Large snake" , "Medium-sweet sherry" .)