Source of stability revealed by Italian choreographer (6)
I believe the answer is:
anchor
'source of stability' is the definition.
(I've seen this before)
'revealed by italian choreographer' is the wordplay.
'revealed by' indicates a hidden word.
'ANCHOR' is hidden in the letters of 'italian choreographer'.
(Other definitions for anchor that I've seen before include "Ship's mooring device" , "reliable means of support" , "TV presenter" , "Stabilise" , "Rear person in a tug-of-war ( 6 )" .)