Statement about rule applied to eggs (6)
I believe the answer is:
avowal
'statement' is the definition.
(avowal is a kind of statement)
'about rule applied to eggs' is the wordplay.
'about' is a reversal indicator.
'rule' becomes 'law' (law is a kind of rule).
'applied to' means one lot of letters go next to another.
'eggs' becomes 'ova' (I've seen this before).
'law'+'ova'='lawova'
'lawova' backwards is 'AVOWAL'.
(Other definitions for avowal that I've seen before include "Affirmed declaration" , "swear!" , "Open declaration or admission" , "Frank confession" , "clear pronouncement" .)