|a soft malleable silvery-grey element of the lanthanide series of metals, occurring in gadolinite and monazite and used in lasers and for doping solid-state devices. Symbol: Tb; atomic no: 65; atomic wt: 158.92534; valency: 3 or 4; relative density: 8.230; melting pt: 1356°C; boiling pt: 3230°C|
|[C19: from New Latin, named after Ytterby, Sweden, village where it was discovered]|
terbium ter·bi·um (tûr'bē-əm)
A soft metallic rare-earth element used in x-ray tubes. Atomic number 65; atomic weight 158.925; melting point 1,359°C; boiling point 3,221°C; specific gravity 8.23; valence 3, 4.
|terbium (tûr'bē-əm) Pronunciation Key
A soft, silvery-gray metallic element of the lanthanide series. It is used in color television tubes, x-ray machines, and lasers. Atomic number 65; atomic weight 158.925; melting point 1,356°C; boiling point 3,123°C; specific gravity 8.229; valence 3, 4. See Periodic Table.