Where does “pertenuis” come from?

pertenuis (Latin) comes from Latin tenuis, from Proto-Indo-European ténh₂us, from Proto-Indo-European tenh₂-, from Proto-Indo-European ten- — to stretch, to extend.

pertenuis (Latin): very thin, fine or slender

Definitions

very thin, fine or slender

Ancestry of “pertenuis”, step by step

Step	Language	Word	Meaning
1	Latin	tenuis	thin, fine, slender; weak, watery; slight,...
2	Proto-Indo-European	ténh₂us	thin
3	Proto-Indo-European	tenh₂-	to stretch, to extend
4	Proto-Indo-European	ten-	to stretch, to extend

Every word from Proto-Indo-European ten- →Every word from Proto-Indo-European tenh₂- →Every word from Proto-Indo-European ténh₂us →