noun.
A direct coal-tar color of the disazo type, derived from dianisidine. It dyes unmordanted cotton reddish violet in an alkaline salt bath.
noun.
In astronomy, an instrument for showing when the sun arrives at the solstitial points.
noun.
A mirror arranged with a telescope and sights so as to flash a reflection of the sun to a great distance. The instrument is used in geodetic triangulation to mark a station. See heliograph, 1.
noun.
A plant of the genus Heliotropium, of the natural order Boraginaceæ.
noun.
The bluish-purple or pinkish-lilac color of some flowers of the heliotrope.
noun.
A mineral, a subspecies of quartz, of a deep-green color, peculiarly pleasant to the eye.