v. [UNDER-1 4 a.] trans. or intr. To undermine; spec. (in coal-mining), to undercut. Also Underholing vbl. sb.

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1398.  Trevisa, Barth. De P. R., XIII. xix. (Bodl. MS.). Vnder hoolinge and vnder crepinge and wastinge vnder brymmes … is icleped Alluuio.

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1891.  Cent. Dict. (as U.S. mining term).

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