Italian number man (4)
I believe the answer is:
This could be a double definition.
'italian number' is the first definition.
The definition suggests a singular noun which matches the answer.
'man' is the second definition.
(I have seen 'A man' mean 'otto' so perhaps 'man' could also mean 'otto')
Can you help me to learn more?
(Other definitions for otto that I've seen before include "Possibly a German" , "He's a German, whichever way you look at it" , "Rose oil; man's name" , "A man" , "Oil made of rose petals" .)