Obs. or rare. Irreg. var. of SUBTERRANEITY.
1646. Sir T. Browne, Pseud. Ep., II. i. 55. I feare we commonly consider subterranities not in contemplations sufficiently respective unto the creation.
1656. Blount, Glossogr., Subterranity, the being under ground.
18778. Henley, in Ballades & Rondeaus (Canterb. Poets), 83. We search the stars for Fame, Or sink her subterranities; The legends still the same:O Vanity of Vanities!