Get really angry and lose your self-control. Derogatory, as implies that it wasn't a reasonable reaction in the circumstances.
After Dad saw my picture on the front of the porno DVD, he completely lost the plot.
by Observer52 August 23, 2005

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Top Definition
To stop acting rationally.
The day of her wedding, I thought Amy was going to lose the plot.
by Tige Gentry July 22, 2006

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To lose the ability to cope with or understand what's going on around you.
Feminist Frequency is complaining about lack of diversity in female character designs in OverWatcth, a game that went out of its way to have the most diversity in female character designs. Way to lose the plot, Feminist Frequency!
by JohnSmith1495 September 03, 2016

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Soft and offensive. Just like you.

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The Urban Dictionary T-Shirt

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