Obs. rare. [prob. echoic] intr. Of the eagle: To scream.

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1677.  Wittie, Gout Raptures, lviii. (1681), 103.

        The Goat did blare, squeak did the Hare,
  And there the Eagle frilled.

2

1688.  R. Holme, Armoury, II. 310/2. The Eagle Frilleth, or Scriketh.

3

  Hence Frill sb., the cry of an eagle.

4

1847.  in Halliwell.

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