The Collaborative International Dictionary
Subterraneously
Subterranean \Sub`ter*ra"ne*an\, Subterraneous \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. -- Sub`ter*ra"ne*ous*ly, adv.
Wiktionary
subterraneously
adv. In a subterraneous manner; underground.
Usage examples of "subterraneously".
Second Pyramid, nearly buried in the drifting sands, yawns subterraneously south-east of the Sphinx.