Catch husband smoking a pipe (6)
I believe the answer is:
hookah
'a pipe' is the definition.
(hookah is a kind of pipe)
'catch husband smoking' is the wordplay.
'catch' becomes 'hook' (hook is a kind of catch).
'husband smoking' becomes 'ah' (I can't justify this - if you can you should give a lot more credence to this answer).
'hook'+'ah'='HOOKAH'
Can you help me to learn more?
(Other definitions for hookah that I've seen before include "Smoking pipe, using water" , "Turkish pipe" , "Water-cooled tobacco pipe" , "Oriental water pipe for smoking" , "Oriental tobacco pipe that cools the smoke" .)