乙脑 yǐnǎo Japanese encephalitis Origin Definitions Defs Strokes Stroke Words Sentences Sents 乙 yǐ abbreviation of 乙型 yǐxíng type B type B; type II; the second of a group of related items, such as blood types or technical specifications脑 腦 nǎo abbreviation of 脑炎 腦炎 nǎoyán encephalitis inflammation of the brain, typically caused by a viral infection