Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
pŏtītus, a, um, Part., in a pass. signif., v. 2. potio.
1. pŏtītus, a, um, Part., from 1. potior.
2. Potitus, i, m., a Roman surname: C. Valerius Potitus, Liv. 4, 53.