Word Study
humus
CIDE DICTIONARY
humus, n. [L., the earth, ground, soil.].
That portion of the soil formed by the decomposition of animal or vegetable matter. It is a valuable constituent of soils. Graham. [1913 Webster]
OXFORD DICTIONARY
humus, n. the organic constituent of soil, usu. formed by the decomposition of plants and leaves by soil bacteria.
Derivative
humusify v.tr. & intr. (-ies, -ied).
Etymology
L, = soil
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