The most pernicious errors in a dataset are the small ones, because nothing about them looks wrong.
数据集中最具危害的错误恰是那些细小的错误，因为它们看上去毫无异常。
Which choice best defines “pernicious”?
C — Highly harmful, esp. subtly.. “pernicious” means Highly harmful, esp. subtly..
Which word means “Highly harmful, esp. subtly.”?
A — pernicious. “pernicious” means Highly harmful, esp. subtly..
pernicious — Highly harmful, esp. subtly.. In Chinese: 有害的；恶性的.
pernicious is pronounced //pəˈnɪʃəs//.
The most pernicious errors in a dataset are the small ones, because nothing about them looks wrong. (数据集中最具危害的错误恰是那些细小的错误，因为它们看上去毫无异常。)
destructive, insidious, ruinous — all close in meaning to pernicious (Highly harmful, esp. subtly.).
beneficial, harmless — each the opposite of pernicious (Highly harmful, esp. subtly.).
Yes. pernicious is on the SAT Prep Difficult list — the higher-register words that decide the hard questions. The Digital SAT does not test vocabulary in isolation; words like this one are tested through Words in Context questions, where you choose the word that completes a passage most logically and precisely.
per(彻底) + nic(害) → 危害深重。