silvery-white metallic element, 1808, coined by English chemist Sir Humphrey Davy (1778-1829) from white magnesia (q.v.), in which it was found, + chemical ending -ium.
magnesium mag·ne·si·um (māg-nē'zē-əm, -zhəm)
n.
Symbol Mg
A light metallic element that burns with a brilliant white flame. Atomic number 12; atomic weight 24.305; melting point 649°C; boiling point 1,090°C; specific gravity 1.74 (at 20°C); valence 2.
magnesium (māg-nē'zē-əm) Symbol Mg A lightweight, moderately hard, silvery-white metallic element of the alkaline-earth group that burns with an intense white flame. It is an essential component of chlorophyll and is used in lightweight alloys, flash photography, and fireworks. Atomic number 12; atomic weight 24.305; melting point 649°C; boiling point 1,090°C; specific gravity 1.74 (at 20°C); valence 2. See Periodic Table. |