Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
falsātus, a, um, Part. and P. a., from 1. falso.
1. falso, āvi, ātum, āre, v. a. [falsus], to falsify (late Lat.): pondera aut mensuras, Dig. 48, 10, 32 fin.: scripturas divinas, Ambros. de Fide, 2, 15, 135: liber falsatus ab haereticis, Hier. in Ruf. 2, 5 al.
Hence, falsātus, a, um, P. a., falsified, Sulp. Sev. de Virt. Monach. 1, 6.