Webster's Revised Unabridged Dictionary · 1913

Culm

Culm (kulm) , noun

[Latin culmus stalk, stem; akin to calamus. SeeHalm.]

(Botany) The stalk or stem of grain and grasses (including the bamboo), jointed and usually hollow.

Culm , noun

[Perh. from Welsh cwlm knot or tie, applied to this species of coal, which is much found in balls or knots in some parts of Wales: compare Old English culme smoke, soot.]

(a)
(Mineralogy) Mineral coal that is not bituminous; anthracite, especially when found in small masses.
(b)
(Mineralogy) The waste of the Pennsylvania anthracite mines, consisting of fine coal, dust, etc., and used as fuel. — Raymond