다고 불리다

be called X by people

불리다 is the passive of 부르다 'to call', and -다고 quotes the description people apply: 무모하다고 불리는 사람들 'people called reckless', 미국에서 가장 가혹하다고 불리는 'said to be the harshest in America'. It attributes the label to others rather than to the speaker, which makes it a favourite of explainer videos introducing a reputation. Compare -라고 불리다, which attaches to a plain noun name instead of a description.

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