Mass producers disheartened old man (6)

I believe the answer is:

gramps

'old man' is the definition.
(thesaurus)

'mass producers disheartened' is the wordplay.
'mass' becomes 'gram' (unit of mass).
'disheartened' means to remove the middle letters (the middle or heart is removed).
'producers' with its centre removed is 'ps'.
'gram'+'ps'='GRAMPS'

I've seen this clue in The Independent.

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