Watch out for intellect (4)
I believe the answer is:
mind
I believe this is a double definition.
'watch out' is the first definition.
(minding is a kind of watching out)
'intellect' is the second definition.
(mind is a kind of intellect)
'for' acts as a link.
(Other definitions for mind that I've seen before include "Object to; take care of" , "Consciousness" , "remember" , "Take offence (at)" , "Take care of; intellect" .)