Meaning
Once you've built a reputation, it sticks — people go on believing it of you with no further effort.
Example
Estudou muito no primeiro ano e agora todos o acham gênio: criou fama e deita na cama.
He studied hard the first year and now everyone thinks he's a genius: once you build a name, it sticks.
Origin
This is a traditional proverb (ditado popular) with no documented author or first attestation; the Aulete dictionary lists it explicitly as a provérbio. It belongs to a wider Iberian family of sayings about reputation — compare "Mais vale boa fama que dourada cama" ("a good name is worth more than a gilded bed").
Sources: Aulete, Lápis Mágico.
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