Is it second nature for a gunman to have one? (9)
I believe the answer is:
automatic
'have one?' is the definition.
Both the answer and definition are adjectives. Maybe there's an association between them I don't understand?
'is it second nature for a gunman' is the wordplay.
I cannot really see how this works, but
'it' could be 't' (abbreviation. e.g. in 'tis) and 't' is found in the answer.
'second' could be 'tic' and 'tic' is found in the answer.
'a' is within the answer.
This explanation may well be incorrect...
'to' is the link.
Can you help me to learn more?
(Other definitions for automatic that I've seen before include "Without volition or conscious control" , "Like George" , "Done without conscious thought" , "Unmanned" , "Functioning without human intervention" .)