Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
vĕtĕrātus, P. a. of vetero.
vĕtĕro, āvi, ātum, 1, v. a. [vetus], to make old (late Lat.): dicendo autem novum veteravit prius, Vulg. Heb. 8, 13.
P. a.: vĕ-tĕrātus, a, um, old, inveterate: mederi ulceribus veteratis, Plin. 32, 10, 52, § 141: caseus, mouldy, Scrib. Comp. 140.