A hard hearted figure, not a lot of money (6)
I believe the answer is:
dollar
'a hard hearted figure' 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?
'a lot of money' is the wordplay.
'a lot of' means to remove the last letter (a lot of but not all of the word).
'money' becomes 'dollars' (I've seen this in another clue).
'dollars' with its last letter taken off is 'DOLLAR'.
'not' is the link.
Can you help me to learn more?
(Other definitions for dollar that I've seen before include "American currency" , "Standard monetary unit of many countries" , "American's ready" , "US currency" , "Economic factors deployed as 'soft power'" .)