A foreign expression oddly securable (5,4)

I believe the answer is:

sacre bleu

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'a foreign expression' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'oddly securable' is the wordplay.
'oddly' indicates anagramming the letters.
'securable' is an anagram of 'SACRE BLEU'.

Can you help me to learn more?

(Other definitions for sacre bleu that I've seen before include "holy cow at Lourdes" , "in Calais, an indication of exasperation" , "Nice exclamation" .)

I've seen this clue in the Sydney Morning Herald.

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