Lady robbed of money, upset for a time (3)

I believe the answer is:

day

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'time' is the definition.
(day is a kind of time)

I don't understand how the remainder of the clue works.

(Other definitions for day that I've seen before include "24 23 acrosses" , "Unit of time" , "Twenty-four hours" , "Born yesterday" , "THIRD PART OF 23" .)

I've seen this clue in the Evening Standard.

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