n. An early form of galley or small ship; a long boat: used with reference to Anglo-Saxon history.n. The principal timber in a ship or boat, extending from stem to stern at the bottom, supporting the whole frame, and consisting of a number of pieces scarfed and bolted together; in iron vessels, the combination of plates corresponding to the keel of a wooden vessel.n. In botany: A central longitudinal ridge along the back of any organ, as a leaf or glume.n. In a papilionaceous corolla, the lower pair of petals, which are more or less united into a prow-shaped body, usually inclosing the stamens and pistil.n. Another structure of similar form, as the lower petal in Polygala. Also called carina. See cut under banner.n. In zoology, a projecting ridge extending longitudinally along the middle of any surface.n. A ship.n. A strong, clumsy boat; a barge such as is used by the colliers at Newcastle in England.n. Hence A measure of coal, 8 Newcastle chaldrons, equal to 424 hundredweight.To plow with a keel, as the sea; navigate.To furnish with a keel.To turn up the keel; show the bottom.To give over; cease.To fall suddenly; tumble down or over, as from fright or a blow, or in a swoon.To make cool; cool; moderate the heat of, as that of the contents of a pot boiling violently by gently stirring them.To moderate the ardor or intensity of; assuage; appease; pacify; diminish.To become cool; cool down.n. In brewing, a broad flat vessel used for cooling liquids; a keelfat.n. Red chalk; ruddle.To mark, as a sheep, with ruddle.n. A variant of kail, 1.n. An obsolete or dialectal form of kill, kiln.n. n. In architecture, the projecting arris of an edge-molding.