The Collaborative International Dictionary of English v.0.48:

Keel \Keel\, v. i. [imp. & p. p. Keeled; p. pr. & vb. n.
   Keeling.]
   1. To traverse with a keel; to navigate.
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   2. To turn up the keel; to show the bottom.
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   To keel over, to upset; to capsize. [Colloq.]
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