I object to a certain course of action (7)

I believe the answer is:

measure

'course of action' is the definition.
(thesaurus)

'i object to a certain' is the wordplay.
'i object' becomes 'me'.
'certain' becomes 'sure' ('sure' can be a synonym of 'certain').
'me'+'a'+'sure'='MEASURE'

(Other definitions for measure that I've seen before include "Find the size" , "capacity" , "Ascertain the length etc." , "Calculate size" , "Extent" .)

I've seen this clue in The Telegraph.

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