1. 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
   - promethium, Pm

Type of: metal, metallic element

• ripping bar
• ripping chisel
• ripple
• ripple effect
• ripple mark
• ripple-grass
• rippled
• rippling
• ripply
• riprap
• ripsaw
• ripsnorter
• riptide
• RIRA
• RISC
• rise
• rise to power
• rise up
• risen
• riser
• riser main
• riser pipe
• riser pipeline
• rishi
• risibility