The Collaborative International Dictionary of English v.0.48:

Kestrel \Kes"trel\ (k[e^]s"tr[e^]l), n. [See Castrel.] (Zool.)
   A small, slender European hawk (Falco alaudarius), allied
   to the sparrow hawk. Its color is reddish fawn, streaked and
   spotted with white and black. Also called windhover and
   stannel. The name is also applied to other allied species.
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   Note: This word is often used in contempt, as of a mean kind
         of hawk. "Kites and kestrels have a resemblance with
         hawks." --Bacon.
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The Collaborative International Dictionary of English v.0.48:

Stannel \Stan"nel\ (-n[e^]l), n. [AS. st[=a]ngella, stangilla;
   properly, stone yeller, i. e., a bird that yells from the
   rocks. See Stone, and Yell, and cf. Stonegall.] (Zool.)
   The kestrel; -- called also standgale, standgall,
   stanchel, stand hawk, stannel hawk, steingale,
   stonegall. [Written also staniel, stannyel, and
   stanyel.]
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         With what wing the staniel checks at it. --Shak.
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