Coomb

[koom, kohm] /kum, koʊm/

noun
1.
.
[koom] /kum/
noun
1.
.
[koom, kohm] /kum, koʊm/
noun, British.
1.
a narrow valley or deep hollow, especially one enclosed on all but one side.
[koom] /kum/
noun, Chiefly Scot. and North England.
1.
soot; coal dust; smut.
2.
dust, especially sawdust or dust from a gristmill.
3.
grease from bearings, axles, etc.
/kuːm/
noun
1.
(mainly Southern English) a short valley or deep hollow, esp in chalk areas
2.
(mainly Northern English) another name for cirque
/kuːm/
noun
1.
variant spellings of coomb
/kuːm/
noun
1.
(dialect, mainly Scot & Northern English) waste material, such as dust from coal, grease from axles, etc
n.

also combe, “deep hollow or valley, especially on flank of a hill,” mainly surviving in place names, from Old English cumb, probably a British word, from Celtic base *kumbos (cf. Welsh cwm in same sense). Cambridge Dictionary of English Place-Names says, “This is usually taken to be a Celtic loan … but there was also OE cumb ‘vessel, cup, bowl,'” which was “probably used in a transferred topographical sense reinforced in western districts by cwm.”