rutile
noun
Forms rutiles
- noun (mineralogy) The most frequent of the three polymorphs of titanium dioxide, crystalizing in the tetragonal system, TiO₂.
Etymology
From Latin rutilus (“red”) because of its common color, named in 1803.
Webster’s 1913
- noun A mineral usually of a reddish brown color, and brilliant metallic adamantine luster, occurring in tetragonal crystals. In composition it is titanium dioxide, like octahedrite and brooklite.
Etymology [L. rutilus red, inclining to golden yellow.]
Sources: Wiktionary · Webster’s 1913 — from the Wiktionary entry “rutile”, CC BY-SA 4.0. Details