Emily Dickinson Lexicon

OX'YD, n. [Gr. οξυς, acid, sharp; οξος, vinegar. The true orthography of this word is oxyd, as originally written by Lavoisier and his associates. No analogy in the language is better established than the uniform translation of the Greek υ into the English y, as in Latin, and it is very absurd to preserve this analogy in oxygen, oxymuriate and hydrogen, and depart from it in oxyd.]

In chimistry, a compound of oxygen and a base destitute of acid and salifying properties.