[ tuh-loo-i-deen, -din ]
/ təˈlu ɪˌdin, -dɪn /

noun Chemistry.

any of three isomeric amines having the formula C7H9N, derived from toluene: used in the dye and drug industries.

Origin of toluidine

First recorded in 1840–50; tolu(ene) + -id3 + -ine2 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for toluidine

British Dictionary definitions for toluidine


/ (tɒˈljuːɪˌdiːn) /


an amine derived from toluene existing in three isomeric forms; aminotoluene. The ortho- and meta- isomers are liquids and the para- isomer is a crystalline solid. All three are used in making dyes. Formula: C 6 H 4 CH 3 NH 2

Word Origin for toluidine

C19: from tolu (ene) + -ide + -ine ²
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Science definitions for toluidine


[ tə-lōōĭ-dēn′ ]

Any of three isomeric compounds containing a benzene ring with a methyl (CH3) and amino (NH2) group attached to it. Toluidine is used to make dyes. Chemical formula: C7H9N.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.