Attend to the intellect (4)
I believe the answer is:
mind
I believe this is a double definition.
'attend to' is the first definition.
(thesaurus)
'the intellect' is the second definition.
('mind' can be a synonym of 'intellect')
(Other definitions for mind that I've seen before include "This can be made up" , "Intelligence" , "Watch - intellect" , "remember" , "Brain" .)