do a number on
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do a number on someone or something
Sl. to damage or harm someone or something. The teacher did a number on the whole class by giving them a pop quiz. Tom did a number on Mary when he went out with Ann.
do a number on somebody/something
to hurt or damage someone or something Dairy foods do a number on my stomach. This case has really done a number on the judge – he looks much older than he did just a few months ago.
do a number on somebody
to treat someone very badly or unfairly I'm not surprised Caroline doesn't like him. He really did a number on her at work.
do a number onSlang
To defeat, abuse, or humiliate in a calculated and thorough way.