n. The most frequent of the three polymorphs of titanium dioxide, crystalizing in the tetragonal system, TiO2.
the GNU version of the Collaborative International Dictionary of English
n. 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 brookite.
The Century Dictionary and Cyclopedia
n. One of the three forms in which titanium dioxid occurs in nature. (See also octahedrite and brookite.)
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. a mineral consisting of titanium dioxide in crystalline form; occurs in metamorphic and plutonic rocks and is a major source of titanium
Word Usage
"The star sapphire does, not the rutile that causes it."