Real Dictionary

keel
countable noun: The keel of a boat is the long, specially shaped piece of wood or steel along the bottom of it.

keel in American English 1
the chief timber or steel piece extending along the entire length of the bottom of a boat or ship and supporting the frame: it sometimes protrudes beneath the hull
to turn over on its side so as to turn up the keel or bottom
noun: a central fore-and-aft structural member in the bottom of a hull, extending from the stem to the sternpost and having the floors or frames attached to it, usually at right angles: sometimes projecting from the bottom of the hull to provide stability

keel in American English 2
a flat-bottomed ship; esp., a low, flat-bottomed coal barge or lighter, used on the Tyne
noun: a keelboat

keel in American English 3
to cool (a hot liquid) as by stirring
transitive verb: to cool, esp. by stirring

keel in American English 4
a red stain used for marking lumber, etc.; ruddle
noun: a red ocher stain used for marking sheep, lumber, etc.; ruddle

keel in British English 1
noun: one of the main longitudinal structural members of a vessel to which the frames are fastened and that may extend into the water to provide lateral stability

keel in British English 2
noun: a flat-bottomed vessel, esp one used for carrying coal

keel in British English 3
to mark with this stain
noun: red ochre stain used for marking sheep, timber, etc

keel in British English 4
verb

keel in British English 5
noun: a fatal disease of young ducks, characterized by intestinal bleeding caused by Salmonella bacteria