Organ for each redhead (3)
I believe the answer is:
ear
'organ' is the definition.
(the ear is an organ)
'each redhead' is the wordplay.
'each' becomes 'ea' (abbreviation).
'redhead' becomes 'r' (the head letter of red).
'ea'+'r'='EAR'
'for' acts as a link.
(Other definitions for ear that I've seen before include "one hears" , "Bit of corn" , "cut" , "Hearing aid?" , "Aural organ" .)