From The Collaborative International Dictionary of English v.0.48:
Winnow \Win"now\ (w[i^]n"n[-o]), v. t. [imp. & p. p. Winnowed
(w[i^]n"n[-o]d); p. pr. & vb. n. Winnowing.] [OE. windewen,
winewen, AS. windwian; akin to Goth. winpjan (in comp.),
winpi-skauro a fan, L. ventilare to fan, to winnow; cf. L.
wannus a fan for winnowing, G. wanne, OHG. wanna. [root]131.
See Wind moving air, and cf. Fan., n., Ventilate.]
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1. To separate, and drive off, the chaff from by means of
wind; to fan; as, to winnow grain.
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Ho winnoweth barley to-night in the threshing floor.
--Ruth. iii.
2.
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2. To sift, as for the purpose of separating falsehood from
truth; to separate, as bad from good.
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Winnow well this thought, and you shall find
This light as chaff that flies before the wind.
--Dryden.
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3. To beat with wings, or as with wings.[Poetic]
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Now on the polar winds; then with quick fan
Winnows the buxom air. --Milton.
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From The Collaborative International Dictionary of English v.0.48:
Winnow \Win"now\, v. i.
To separate chaff from grain.
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Winnow not with every wind. --Ecclus. v.
9.
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