to sort things out on one's own, to get oneself out of trouble (vulgar
Ninguém vai te salvar, se desenmerde!
Nobody's going to save you, figure it out!
Desenmerdar is a direct import from French se démerder, an informal verb attested from around 1900 and built from dé- plus merde — literally "to get yourself out of the mess."
Source: Wiktionary — démerder.
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