oriskany

from The Century Dictionary.

• noun In the geology of New York, an arenaceous or calcareo-arenaceous member of the rock series, in the eastern part of the State lying above the Helderberg limestones and below the Esopus and Schoharie grits, in the western part lying above the Waterlime series, with which it is unconformable, and beneath the Onondaga limestone.

from the GNU version of the Collaborative International Dictionary of English.

• adjective (Geol.) Designating, or pertaining to, certain beds, chiefly limestone, characteristic of the latest period of the Silurian age.
• adjective a subdivision of the American Paleozoic system intermediate or transitional in character between the Silurian and Devonian ages. See Chart of Geology.