Note about Italian religion (5)
I believe the answer is:
faith
'religion' is the definition.
(I've seen this before)
'note about italian' is the wordplay.
'note' becomes 'fah' (fourth note in sol-fa notation, anglicized version**).
'about' indicates putting letters inside.
'italian' becomes 'it'.
'fah' going around 'it' is 'FAITH'.
(Other definitions for faith that I've seen before include "It goes with hope and charity" , "Unshakeable belief" , "'..... will move mountains'" , "religion" , "Confidence" .)