前寒武纪 qiánhánwǔjì Precambrian Origin Definitions Defs Strokes Stroke Words Sentences Sents 前 qián prepositionlocative before (bound form) ago; before; earlier; previously寒武纪 寒武紀 hánwǔjì Cambrian The Cambrian geological period, the first period of the Paleozoic Era; it began roughly 541 million years ago and was named after the Latin for Wales.