"unyielding, persistent, resolute" (in holding to a purpose, opinion, course of action, etc.), 1620s, from pertinacy "stubbornness" (late 14c.), from Latin pertinacia, from pertinax "very firm, tenacious" (see pertinacity) + -ous. Related: Pertinaciously.
the most vocal and pertinacious of all the critics
persuasible
persuasion
persuasive
pert
pertain
pertinacious
pertinacity
pertinence
pertinency
pertinent
perturb
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