Word: 未知数 (wèizhīshù) Traditional: 未知數 未知数 dictionary entry wèizhīshù unknown number; an unknown Full dictionary entry for 未知数 Example sentences using 未知数 2 sentences, showing page 1 of 1. 他能不能按时到，还是个未知数。 Tā néng bùnéng ànshí dào, háishi gè wèizhīshù. Whether he can arrive on time is still an uncertainty. 这道数学题要先算出未知数的值。 Zhè dào shùxué tí yào xiān suàn chū wèizhīshù de zhí. In this math problem you must first work out the value of the unknown.