apostasis Save DMLBS apostasis [ἀπόστασις] 1 rejection of monastic rule (= apostasia c). 12‥ ut ‘i [? l. ~ia] sua relicta ad monasteria redeant Conc. Scot. II 60. 2 ulcer (= apostema). in laboriosis febribus ~es fiunt Gilb. I 69. 2.