- a rare-earth metallic element discovered in samarskite. Symbol: Sm; atomic weight: 150.35; atomic number: 62; specific gravity: 7.49.
- a silvery metallic element of the lanthanide series occurring chiefly in monazite and bastnaesite and used in carbon-arc lighting, as a doping agent in laser crystals, and as a neutron-absorber. Symbol: Sm; atomic no: 62; atomic wt: 150.36; valency: 2 or 3; relative density: 7.520; melting pt: 1074°C; boiling pt: 1794°C
n. Symbol Sm
- A metallic rare-earth element used in alloys, in infrared absorbing glass, and as a neutron absorber in certain nuclear reactors. Atomic number 62.
- A silvery-white metallic element of the lanthanide series that exists in several forms and has seven naturally occurring isotopes. It is used to make glass that absorbs infrared light and to absorb neutrons in the fuel rods of nuclear reactors. Atomic number 62; atomic weight 150.36; melting point 1,072°C; boiling point 1,791°C; specific gravity approximately 7.50; valence 2, 3. See Periodic Table.