1. [ noun ] one thousandth (1/1,000) gram
Synonyms: milligram
Related terms: metric_weight_unit grain microgram
2. [ noun ] (chemistry) a light silver-white ductile bivalent metallic element; in pure form it burns with brilliant white flame; occurs naturally only in combination (as in magnesite and dolomite and carnallite and spinel and olivine)
Synonyms: atomic_number_12 magnesium
Related terms: metallic_element magnesite dolomite olivine periclase spinel carnallite