variants: or coomb \ ˈküm \
plural -s

Definition of coom

 (Entry 1 of 2)

1 dialectal, British
a : soot, smut
b : coal dust or coal slack
2 : grease exuding from axle boxes or bearings
variants: or coomb \ " \
plural -s

Definition of coom (Entry 2 of 2)

: the wooden centering or frame on which a masonry arch is built

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History and Etymology for coom

Noun (1)

Middle English culme

Noun (2)

origin unknown

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Cite this Entry

“Coom.” Dictionary, Merriam-Webster, Accessed 29 Oct. 2020.

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