Simple past tense and past participle of keel.(verb)
Furnished with a keel, especially a keel of a specified type(adjective)
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Use "keeled" in a sentence
"Although he makes the point that the periphery is "hardly to be called keeled", to me "carinated", "angular" and "keeled" all mean more or less the same thing, especially when the degree of carination is variable."
"Its bays are square, and the groin ribs consist each of three round mouldings, of which the most prominent is 'keeled';  but what is most remarkable is that there are also ridge-ribs, which are not usually found before the thirteenth century, and it has been suggested  that this is the earliest instance of their employment."
"He looked kind of keeled over, his head on a cement step."