Rodent hunter carrying large snake (7)
I believe the answer is:
rattler
'snake' is the definition.
(I know that rattler is a type of Crotalinae)
'rodent hunter carrying large' is the wordplay.
I cannot quite see how this works, but
'rodent' could be 'rat' (rat is a kind of rodent) and 'rat' is present in the answer.
'large' could be 'l' (eg in clothes sizes) and 'l' is found within the answer.
The remaining letters 'ter' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for rattler that I've seen before include "Poisonous American" , "that makes one frightened" , "Dangerous snake" , "US snake (colloq.)" , "A noisy American snake" .)