What is "falco sacer"

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. (Zo["o]l.)

   1. A falcon ( Falco sacer) native of Southern Europe and Asia, closely resembling the lanner.

      Note: The female is called chargh, and the male charghela, or sakeret.

   2. The peregrine falcon. [Prov. Eng.]

2. (Mil.) A small piece of artillery.
   --Wilhelm.

   On the bastions were planted culverins and sakers.
   --Macaulay.

   The culverins and sakers showing their deadly muzzles over the rampart.
   --Hawthorne.