v. rare. [UNDER-1 4 a, b, 8 a.] To search or seek under or into; to investigate.

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1609.  Daniel, Civ. Wars, III. iv. Whil’st th’ vnder-searching water, working-on, Beares (proudly) downe, all that was idly don.

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1648.  Hexham, II. Ondertasten, to Examine, or Vndersearch.

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