dinitrobenzene

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Any of three isomeric compounds, C₆H₄(NO₂)₂, made from a mixture of nitric acid, sulfuric acid, and heated benzene and used in celluloid manufacture, in dyes, and in organic synthesis.

from The Century Dictionary.

• noun A compound, C₆H₄ (NO₂)₂, derived from benzene by the substitution of two nitro-groups for two hydrogen atoms.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun organic chemistry Any of three isomeric aromatic nitro compounds C6H4(NO2)2 formed by the nitration of benzene; they are used in the manufacture of dyes etc