Origin: 1495–1505; < LL pertinācitās, for L pertinācia stubbornness, perseverance (> obs. pertinacy), equiv. to pertināci- (s. of pertināx) steadfast, stubborn + -tās-ty2. See per-, tenacity
Synonyms: firmness, determination, resolution. See perseverance.
per·ti·nac·i·ty (pûr'tn-ās'ĭ-tē) n. The quality or state of being pertinacious: "Again and again ... with the inexorable pertinacity of a child ... did he renew his efforts"(Nathaniel Hawthorne).