Definition of siderite

• n. - Carbonate of iron, an important ore of iron occuring generally in cleavable masses, but also in rhombohedral crystals. It is of a light yellowish brown color. Called also sparry iron, spathic iron.
• n. - A meteorite consisting solely of metallic iron.
• n. - An indigo-blue variety of quartz.
• n. - Formerly, magnetic iron ore, or loadstone.
• n. - Any plant of the genus Sideritis; ironwort.