Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
1. ăbortĭo, ōnis, f. [aborior, in the sense of misbirth], premature delivery, miscarriage, Plaut. Truc. 1, 2, 98; Cic. Clu. 12; Dig. 48, 19, 38, § 5.
2. ăbortĭo, īre, 4, v. n. [aborior, in the sense of misbirth] to miscarry, Vulg. Job, 21, 10; in Plin. 8, 51, 77, aboriendi is the true reading (Jan.).