pindexpromethium./pruh-mee-thee-uhm/US // prəˈmi θi əm //UK // (prəˈmiːθɪəm) //钷,原锂,锂,钷钷Definitionsn.noun · 名词1. Chemistry.›a rare-earth, metallic, trivalent element. Symbol: Pm; atomic number: 61.Level 5More words in p →