Orthocarbonic
Or`tho`car`bon´ic
a. 1. (Chem.) Designating a complex ether, C.(OC2H5)4, which is obtained as a liquid of a pleasant ethereal odor by means of chlorpicrin, and is believed to be a derivative of the hypothetical normal carbonic acid, C.(OH)4.
Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.