From Longman Dictionary of Contemporary Englishcoal tarˈcoal tar noun [uncountable] TIMa thick black sticky liquid made by heating coal without air, from which many drugs and chemical products are made coal tar soap
Examples from the Corpus
coal tar• Janice smelt of piety and coal tar soap.• A new family shampoo comes by way of Cuticura Medicated Shampoo, with an original coal tar formula that helps prevent dandruff.• She was using the best guest soap every day instead of the coal tar soap which was to be used by family.• Getting rid of PAHs requires the replacement of old cast iron mains lined with coal tar paper. 