Where does “pertinacy” come from?

pertinacy (English) comes from Latin pertinēre, from Latin per, from Latin Ad, from Latin illic, from Latin ille, from Latin olle, from Proto-Italic *olnos — that.

pertinacy (English): Obsolete form of pertinacity; The quality or...

Definitions

Obsolete form of pertinacity; The quality or...

Ancestry of “pertinacy”, step by step

Step	Language	Word	Meaning
1	Latin	pertinēre	—
2	Latin	per	through, by means of; throughout, during
3	Latin	Ad	toward, to
4	Latin	illic	he, she, it, yonder, that, overthere; in that...
5	Latin	ille	that; those; "; demonstrative pronoun "; that...
6	Latin	olle	Archaic form of ille
7	Proto-Italic	*olnos	that

Every word from Proto-Italic *olnos →Every word from Latin olle →Every word from Latin ille →