Cut Sophia Loren's initials on a tree (5)
I believe the answer is:
slash
'cut' is the definition.
(slash is a kind of cut)
'sophia loren's initials on a tree' is the wordplay.
'initials' says to take the initial letters.
'on' means one lot of letters go next to another.
'a tree' becomes 'ash' (ash is a kind of tree).
The initial letters of 'sophia loren' is 'sl'.
'sl'+'ash'='SLASH'
(Other definitions for slash that I've seen before include "Legendary guitarist" , "Drastically prune" , "Punctuation mark" , "Lacerate" , "rent" .)