American English

Definition of promethium noun from the Oxford Advanced American Dictionary

 

promethium

 noun
noun
NAmE//prəˈmiθiəm//
 
[uncountable] (symbol Pm)
 
jump to other results
a chemical element. Promethium is a radioactive metal that was first produced artificially in a nuclear reactor and is found in small amounts in nature.
See the Oxford Advanced Learner's Dictionary entry: promethium