Deviating from norm? Not in the Royal Engineers (5)

I believe the answer is:

outre

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'deviating from norm?' is the definition.
I can't tell whether this definition defines the answer.

'not in the royal engineers' is the wordplay.
'not in' becomes 'out' ('out' is the opposite to 'in').
'the royal engineers' becomes 'RE' (abbreviation).
'out'+'re'='OUTRE'

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(Other definitions for outre that I've seen before include "kinky?" , "Unusual, a bit shocking" , "Conspicuously unconventional" , "Extravagant; bizarre" , "flamboyant" .)

I've seen this clue in The Times.

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