Gangster and nutter — one put out diary (7)
I believe the answer is:
almanac
'out diary' is the definition.
The definition and answer can be both related to communication as well as being singular nouns.
Maybe there's an association between them I don't understand?
'gangster and nutter one' is the wordplay.
I cannot really see how this works, but
'gangster' could be 'al' (Al Capone) and 'al' is located in the answer.
'and' could be 'n' (common abbreviation for 'and') and 'n' is located in the answer.
'one' could be 'a' (a thing is one thing) and 'a' is found in the answer.
The remaining letters 'mac' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
'put' acts as a link.
Can you help me to learn more?
(Other definitions for almanac that I've seen before include "Annual calendar or handbook" , "Annual publication providing information like Old Moore's" , "Annual publication with mixed data, forecasts etc." , "Statistical annual" , "Sailor's or farmer's calendar" .)