Etymology From Middle English culme, colme (“fragments of coal”), of uncertain origin. Probably from Old English *colm, related to Old English col (“coal”). Alternatively, perhaps 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.
1
Waste coal, used as a poor quality fuel.
Holonyms: spoils, tailings
Here he lay down on a place soft with culm, to take his contemplated rest, and, before he was aware of it, sleep had descended on him, overpowered him, and bound him fast.1887, Homer Greene, chapter XXI, in Burnham Breaker:
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The spoils from which such low-quality coal can be retrieved.
culm dump
culm pile
1 more example
Q. (By Mr. Manager FLOYD.) Mr. Rittenhouse, what do you mean in your report by the slush pile?—A. I mean the waste that goes through the finest mesh that they use. It is called tailings; it is called slush. Q. State the origin and meaning of the word "culm" of the term "culm dump."—A. Culm meant and means anything that is waste. Back in the early days it was called culm when they put chestnut in the pile; it was all the waste rock and the material that was thrown out in the breaker; rough coal and slate were thrown indiscriminately on this pile, and it was called culm pile. As the years went by and they used chestnut coal, when that was taken up the coal before it went to the culm dump. It was the same way with pea coal; following that, buckwheat No. 1; then again No. 2, and again No. 8; so that now what represents culm or culm pile, as it goes by, is the finest sand or silt as it goes through three thirty-seconds or the eighth of an inch or the sixteenth of an inch mesh, whatever they happen to use. Sometimes that is separated, and when it is separated and the slate in larger pieces is not mixed with it it is a slush. Q. In the common acceptation of the term a culm dump is the material in the dump made from coal mines, including particles of coal and other waste, is it?—A. Yes, sir.1913 [1912 December 9], United States Senate, “Congressional Record—Senate”, in Congressional Record: Containing the Proceedings and Debates of the Sixty-Second Congress, Third Session, volume XLIX, page 321:
3
Anthracite, especially when found in small masses.
Etymology Borrowed from Latin culmus. Doublet of French calame, calamus, and haulm; further related to caramel, chalumeau and shawm.
1
Biology, Botany, Natural sciences The stem of a plant, especially of grass or sedge.
[…] because, upon hearing him out, she sank down on the lawn in an impossible posture, examining a grass culm and frowning, he had taken his words back at once; […]1962, Vladimir Nabokov, Pale Fire, page 150: