Odd thing to say (6,6)

I believe the answer is:

casual remark

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'odd thing' is the definition.
I know nothing about this answer so I cannot tell whether this works.

'to say' is the wordplay.
'to' becomes 'casual' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'say' becomes 're-mark' (remarking is a kind of saying).
'casual'+'remark'='CASUAL REMARK'

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

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