Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
sentōsus (-tŭōsus), a, um, adj. [sentis], 
- I. full of thorns, thorny (late Lat.), Paul. Nol. Carm. 6,310; Fulg. Myth. prol.
 
- II.  Trop., form sentuosus: stricto et sentuoso brevitatis vinculo, Boëth. in Porphyr. Dial. 1, p. 12.