coal tar

noun
1.
a thick, black, viscid liquid formed during the distillation of coal, that upon further distillation yields compounds, as benzene, anthracene, and phenol, from which are derived a large number of dyes, drugs, and other synthetic compounds, and that yields a final residuum (coal-tar pitch) which is used chiefly in making pavements.
Origin
1775-85
Related forms
coal-tar, adjective
British Dictionary definitions for coal tar

coal tar

noun
1.
a black tar, produced by the distillation of bituminous coal, that can be further distilled to yield benzene, toluene, xylene, anthracene, phenol, etc
coal tar in Medicine

coal tar n.
A viscous black liquid containing numerous organic compounds that is obtained by the destructive distillation of coal and that has many uses including as raw material for many dyes, drugs, and paints.

coal tar in Science
coal tar  
A thick, sticky, black liquid obtained through the destructive distillation (heating in the absence of air) of coal. It is used as a source of many organic compounds, such as benzene, naphthalene, and phenols, which are used in dyes, drugs, and other compounds.
Encyclopedia Article for coal tar

principal liquid product resulting from the carbonization of coal, i.e., the heating of coal in the absence of air, at temperatures ranging from about 900 to 1,200 C (1,650 to 2,200 F). Many commercially important compounds are derived from coal tar.

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