Sub`ter*ra"ne*an (?), Sub`ter*ra"ne*ous (?), a. [L. subterraneus; sub under + terra earth. See Terrace.]
Being or lying under the surface of the earth; situated within the earth, or under ground; as, subterranean springs; a subterraneous passage.
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Sub`ter*ra"ne*ous*ly, adv.
© Webster 1913.