egregious
adjective formal disapproving uk/ɪˈɡriː.dʒəs/ us/ɪˈɡriː.dʒəs/
（错误等）极其严重的，极坏的，令人震惊的
extremely bad in a way that is very noticeable
It was an egregious error for a statesman to show such ignorance. 一位政界人士表现得如此无知，犯这种错误是极不应该的。
Synonyms: flagrantglaringgross