真空管 Save Sign in to save words zhēnkōngguǎn ㄓㄣ ㄎㄨㄥ ㄍㄨㄢˇ vacuum tube thermionic valve Character by character 真(zhēn)really 空(kōng)empty 管(guǎn)surname Guan A Chinese word or character, or English Search Sources CC-CEDICT, CC BY-SA 4.0 pinyinjs, Apache-2.0