• Webster's Revised Unabridged Dictionary
    • v. t Obumbrate To shade; to darken; to cloud.
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Century Dictionary and Cyclopedia
    • obumbrate To overshadow; shade; darken; cloud.
    • obumbrate In zoology, lying under a projecting part: specifically said of the abdomen when it is concealed under the posterior thoracic segments, as in certain Arachnida.
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Chambers's Twentieth Century Dictionary
    • v.t Obumbrate ob-um′brāt to overshadow, to darken
    • adj Obumbrate lying under some projecting part, as the abdomen of certain spiders
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Webster's Revised Unabridged Dictionary
L. obumbratus, p. p. of obumbrare, to overshadow, cloud; ob + umbrare, to shade