The Collaborative International Dictionary of English v.0.48:

Flock \Flock\, v. i. [imp. & p. p. Flocked; p. pr. & vb. n.
   Flocking.]
   To gather in companies or crowds.
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         Friends daily flock.                     --Dryden.
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   Flocking fowl (Zool.), the greater scaup duck.
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