Old English age could mix perfume (3,2,7)

I believe the answer is:

eau de cologne

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'perfume' is the definition.
(eau de cologne is a kind of perfume)

I can't explain the rest of the clue.

(Other definitions for eau de cologne that I've seen before include "Mild perfume" , "Perfumed mixture of alcohol and essential oils" , "Perfumed liquid" , "Scented toilet water" , "Perfumed toilet water" .)

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

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