Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
ŏvātĭo, ōnis, f. [ovo], an ovation, i. e. a lesser triumph, in which the general, after an easy, bloodless victory, or after a victory over slaves, made his public entrance into the city, not in a chariot, as in the greater triumph, but simply on horseback or on foot. The token of a bloodless victory was a wreath of myrtle around his brows; cf. Fest. p. 195 Müll.; Gell. 5, 6, 20; Plin. 15, 29, 38, § 125: fuit de servis ovatione contentus, Flor. 3, 19, 8.