Expensive dropping daughter's organ (3)
I believe the answer is:
ear
'organ' is the definition.
(the ear is an organ)
'expensive dropping daughter's' is the wordplay.
'expensive' becomes 'dear' (similar in meaning).
'dropping' is a deletion indicator.
'daughter' becomes 'd' (genealogical abbreviation).
'dear' with 'd' removed is 'EAR'.
(Other definitions for ear that I've seen before include "Speculator ignoring British" , "Part of cereal plant containing seed" , "Spike (wheat)" , "Attention; an organ" , "Seed-bearing part of wheat" .)