One thousand turn out better (7)

I believe the answer is:

improve

'better' is the definition.
(I know that better can be written as improve)

'one thousand turn out' is the wordplay.
'one' becomes 'i' (Roman numeral).
'thousand' becomes 'm' (Roman numeral for a thousand).
'turn out' becomes 'prove' (synonyms).
'i'+'m'+'prove'='IMPROVE'

(Other definitions for improve that I've seen before include "Enhance" , "Make progress" , "reform" , "Ameliorate" , "Polish" .)

I've seen this clue in The Globe and Mail.

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