sav·ant /ˈsævənt $ səˈvɑːnt, sæ-/ noun [countableC] formal 1. INTELLIGENTsomeone who knows a lot about a subject 博学之士,专家,学者
2. someone who has mental problems and may have lower intelligence than average, but who can do one thing very well, such as adding numbers very quickly 天才白痴〔指独通一行的精神病人或独开一窍的弱智者〕