The definition of pertinacious is a determined person, or a person's stubborn hold onto their opinion.(adjective)
An example of pertinacious is a car salesman who won't take no for an answer.
See pertinacious in Webster's New World College Dictionary
Origin: < L pertinax (gen. pertinacis), firm < per-, intens. + tenax, holding fast < tenere, to hold: see thin
See pertinacious in American Heritage Dictionary 4
Origin: From Latin pertināx, pertināc-
Origin: : per-, per-
Origin: + tenāx, tenacious (from tenēre, to hold; see ten- in Indo-European roots).
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