Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
Picti, ōrum, m. [pingo, the painted people], a people of Britain,the Picts or ancient Caledonians (so named from their practice of tattooing themselves), Amm. 20, 1, 1;Claud. III. Cons. Hon. 54;id. Laud. Stil. 2, 254.