The Collaborative International Dictionary of English v.0.48:

Glean \Glean\, v. t. [imp. & p. p. Gleaned; p. pr. & vb. n.
   Gleaning.] [OE. glenen, OF. glener, glaner, F. glaner, fr.
   LL. glenare; cf. W. glan clean, glanh?u to clean, purify, or
   AS. gelm, gilm, a hand?ul.]
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   1. To gather after a reaper; to collect in scattered or
      fragmentary parcels, as the grain left by a reaper, or
      grapes left after the gathering.
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            To glean the broken ears after the man
            That the main harvest reaps.          --Shak.
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   2. To gather from (a field or vineyard) what is left.
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   3. To collect with patient and minute labor; to pick out; to
      obtain.
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            Content to glean what we can from . . . experiments.
                                                  --Locke.
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