Synonyms/Hypernyms (Ordered by Estimated Frequency) of noun promethium

1 sense of promethium

Sense 1
promethium, Pm, atomic number 61 -- (a soft silvery metallic element of the rare earth group having no stable isotope; was discovered in radioactive form as a fission product of uranium)
       => metallic element, metal -- (any of several chemical elements that are usually shiny solids that conduct heat or electricity and can be formed into sheets etc.)