Fellow follows heart in fall recess (6)
I believe the answer is:
alcove
'recess' is the definition.
(alcove is a kind of recess)
'fellow follows heart in fall' is the wordplay.
'fellow' becomes 'cove' (British slang term).
'follows' means one lot of letters go next to another.
'heart in' says to take the centre.
The middle letters of 'fall' are 'al'.
'cove' put after 'al' is 'ALCOVE'.
(Other definitions for alcove that I've seen before include "Recessed area" , "Small opening off a larger room" , "nook" , "bay" , "compartment" .)