Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
ornātĭo, ōnis, f. [orno], an adorning, adornment, ornament (not ante-Aug., and very rare), Vitr. 5, 8, 8: ornationes templi, Inscr. Orell. 775: STATVAE, Inscr. ap. Nov. Lett. di Firenze, t. ii. p. 600.