xylidine

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Any of six toxic isomers, (CH₃)₂C₆H₃NH₂, derived from xylene, used chiefly as dye intermediates.
2. n. Any of various mixtures of xylidine isomers.

Century Dictionary and Cyclopedia

1. n. In chem., an amine derivative from the hydrocarbon xylene, itself obtained from coal-tar. The general formula for xylidine is C₆H₃(CH₃)₂NH₂, but there are six isomeric forms, of which two form the greater part of the oily liquid industrially known under this name and used in the manufacture of artificial dyestuffs.
2. n. Same as xyloidine.

Wiktionary

1. n. organic chemistry Any of six isomeric aromatic amines (CH3)2C6H3NH2 derived from the xylenes

GNU Webster's 1913

1. n. (Chem.) Any one of six metameric hydrocarbons, (CH3)2.C6H3.NH2, resembling aniline, and related to xylene. They are liquids, or easily fusible crystalline substances, of which three are derived from metaxylene, two from orthoxylene, and one from paraxylene. They are called the amido xylenes.