keel

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Nautical The principal structural member of a ship, running lengthwise along the center line from bow to stern, to which the frames are attached.
2. n. Nautical A ship.
3. n. A structure, such as the breastbone of a bird, that resembles a ship's keel in function or shape.
4. n. The principal structural member of an aircraft, resembling a ship's keel in shape and function.
5. n. A pair of united petals in certain flowers, as those of the pea.
6. v. Nautical To capsize or cause to capsize.
7. keel over To collapse or fall into or as if into a faint.
8. n. Nautical A freight barge, especially one for carrying coal on the Tyne River in England.
9. n. Nautical The load capacity of this barge.
10. n. A British unit of weight formerly used for coal, equal to about 21.2 long tons.
11. v. Chiefly British To make cool.

Century Dictionary and Cyclopedia

1. n. An early form of galley or small ship; a long boat: used with reference to Anglo-Saxon history.
2. 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.
3. n. In botany: A central longitudinal ridge along the back of any organ, as a leaf or glume.
4. 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.
5. n. Another structure of similar form, as the lower petal in Polygala. Also called carina. See cut under banner.
6. n. In zoology, a projecting ridge extending longitudinally along the middle of any surface. Specifically, in ornithology: The gonys of the bill.
7. n. A ship.
8. n. A strong, clumsy boat; a barge such as is used by the colliers at Newcastle in England.
9. n. Hence A measure of coal, 8 Newcastle chaldrons, equal to 424 hundredweight. This would be about 15½ London chaldrons of 36 bushels. But a statute of 1421 makes the keel 20 chaldrons (chaldre).
10. To plow with a keel, as the sea; navigate.
11. To furnish with a keel.
12. To turn up the keel; show the bottom.
13. To give over; cease.
14. To fall suddenly; tumble down or over, as from fright or a blow, or in a swoon.
15. To make cool; cool; moderate the heat of, as that of the contents of a pot boiling violently by gently stirring them.
16. To moderate the ardor or intensity of; assuage; appease; pacify; diminish.
17. To become cool; cool down.
18. n. In brewing, a broad flat vessel used for cooling liquids; a keelfat.
19. n. Red chalk; ruddle.
20. To mark, as a sheep, with ruddle.
21. n. A variant of kail, 1.
22. n. An obsolete or dialectal form of kill, kiln.
23. n. In architecture, the projecting arris of an edge-molding.

Wiktionary

1. n. a large beam along the underside of a ship’s hull from bow to stern
2. n. sometimes, a rigid, flat piece of material anchored to the lowest part of the hull of a ship to give it greater control and stability
3. n. a type of flat-bottomed boat
4. n. something similar to chalk or crayon used to mark pavement
5. v. intransitive, followed by "over" to collapse, to fall

GNU Webster's 1913

1. v. obsolete To cool; to skim or stir.
2. n. A brewer's cooling vat; a keelfat.
3. n. (Shipbuilding) A longitudinal timber, or series of timbers scarfed together, extending from stem to stern along the bottom of a vessel. It is the principal timber of the vessel, and, by means of the ribs attached on each side, supports the vessel's frame. In an iron vessel, a combination of plates supplies the place of the keel of a wooden ship. See Illust. of keelson.
4. n. Fig.: The whole ship.
5. n. engraving A barge or lighter, used on the Tyne for carrying coal from Newcastle; also, a barge load of coal, twenty-one tons, four cwt.
6. n. (Bot.) The two lowest petals of the corolla of a papilionaceous flower, united and inclosing the stamens and pistil; a carina. See Carina.
7. n. (Nat. Hist.) A projecting ridge along the middle of a flat or curved surface.
8. n. (Aeronautics) In a dirigible, a construction similar in form and use to a ship's keel; in an aëroplane, a fin or fixed surface employed to increase stability and to hold the machine to its course.
9. v. To traverse with a keel; to navigate.
10. v. To turn up the keel; to show the bottom.

WordNet 3.0

1. n. one of the main longitudinal beams (or plates) of the hull of a vessel; can extend vertically into the water to provide lateral stability
2. v. walk as if unable to control one's movements
3. n. the median ridge on the breastbone of birds that fly
4. n. a projection or ridge that suggests a keel