Part of a mermaid costume (4)

I believe the answer is:
tail
(Other definitions for tail that I've seen before include "Caudal fin" , "Last, rear, part" , "Shadow" , "Animal's elongated appendage" , "Follow; end part" .)
I believe the answer is:
tail
(Other definitions for tail that I've seen before include "Caudal fin" , "Last, rear, part" , "Shadow" , "Animal's elongated appendage" , "Follow; end part" .)