The Collaborative International Dictionary of English v.0.48:

Swoop \Swoop\, v. t. [imp. & p. p. Swooped; p. pr. & vb. n.
   Swooping.] [OE. swopen, usually, to sweep, As. sw[=a]pan to
   sweep, to rush; akin to G. schweifen to rove, to ramble, to
   curve, OHG. sweifan to whirl, Icel. sveipa to sweep; also to
   AS. sw[imac]fan to move quickly. Cf. Sweep, Swift, a. &
   n., Swipe, Swivel.]
   1. To fall on at once and seize; to catch while on the wing;
      as, a hawk swoops a chicken.
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   2. To seize; to catch up; to take with a sweep.
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            And now at last you came to swoop it all. --Dryden.
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            The grazing ox which swoops it [the medicinal herb]
            in with the common grass.             --Glanvill.
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