Hanging spike of frozen water (6)
I believe the answer is:
icicle
'hanging spike of frozen water' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for icicle that I've seen before include "Hanging ice; stalactite" , "Winter hanger" , "A pendant spike of frozen water" , "Frozen water drip" , "Hanging drop of cold water" .)