The Collaborative International Dictionary of English v.0.48:

Saker \Sa"ker\ (s[=a]"k[~e]r), n. [F. sacre (cf. It. sagro, Sp.
   & Pg. sacre), either fr. L. sacer sacred, holy, as a
   translation of Gr. "ie`rax falcon, from "iero`s holy, or more
   probably from Ar. [,c]aqr hawk.] [Written also sacar,
   sacre.]
   1. (Zool.)
      (a) A falcon (Falco sacer) native of Southern Europe and
          Asia, closely resembling the lanner.
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   Note: The female is called chargh, and the male
         charghela, or sakeret.
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      (b) The peregrine falcon. [Prov. Eng.]
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   2. (Mil.) A small piece of artillery. --Wilhelm.
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            On the bastions were planted culverins and sakers.
                                                  --Macaulay.
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            The culverins and sakers showing their deadly
            muzzles over the rampart.             --Hawthorne.
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