Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
ējūrātĭo (ējĕrātio, Tert. Spect. 4; cf. ejuro), ōnis, f. [ejuro, II.], an abjuring, i. e. a resigning, abdication, laying down of an office (post-Aug.).