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definitions

semibituminous coal

[sem-ee-bi-too-muh-nuh s, -tyoo-, sem-ahy-, sem-ee-, sem-ahy-]
noun
  1. a coal intermediate between bituminous and anthracite coal in hardness, yielding the maximum heat of any ordinary steam coal.

Origin of semibituminous coal

First recorded in 1855–60; semi- + bituminous
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018