Good line erased, dreadfully vague (11)

I believe the answer is:

generalised

'vague' is the definition.
('vague'->'generalized' is in my internal thesaurus and 'ize'->'ise')

'good line erased dreadfully' is the wordplay.
'good' becomes 'g' (abbreviation).
'dreadfully' indicates anagramming the letters.
'line'+'erased'='lineerased'
'lineerased' with letters rearranged gives 'eneralised'.
'g'+'eneralised'='GENERALISED'

(Another definition for generalised that I've seen is " was not specific".)

I've seen this clue in The Times.

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