subterraneous

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

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