Dad’s sinister insult after losing face (4)

I believe the answer is:

aunt

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'face' is the definition.
The answer and definition can be both people as well as being singular nouns.
Maybe they are linked in a way I don't understand?

I don't understand the rest of the clue.

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(Other definitions for aunt that I've seen before include "Female relative" , "Tuna (anag.)" , "Tuna gone bad for the relative" , "Sister of father/mother" , "kinswoman" .)

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

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