Emily Dickinson Lexicon

A-POS'TA-SY, n. [Gr. αποστασις, a defection, of αφιστημι, to depart, απο, and ιστημι.]

1. An abandonment of what one has professed; a total desertion, or departure from one's faith or religion.
2. The desertion from a party to which one has adhered.
3. Among physicians, the throwing off of exfoliated or fractured bone, or the various solution of disease. – Coxe.
4. An abscess. – Encyc.