The Collaborative International Dictionary of English v.0.48:

Unearth \Un*earth"\, v. t. [imp. & p. p. Unearthed; p. pr. &
   vb. n. Unearthing.] [1st pref. un- + earth.]
   To drive or draw from the earth; hence, to uncover; to bring
   out from concealment; to bring to light; to disclose; as, to
   unearth a secret.
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         To unearth the roof of an old tree.      --Wordsworth.
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