Where does “pore” come from?

pore (Middle English) comes from Old French pore, from Latin porus, from Ancient Greek πόρος, from Ancient Greek πείρω, from Proto-Hellenic *péryō.

Ancestry of “pore”, step by step

Step	Language	Word	Meaning
1	Old French	pore	pore
2	Latin	porus	pore, passage in the body; tufa
3	Ancient Greek	πόρος	a means of passage, passageway, way, opening;...
4	Ancient Greek	πείρω	I pierce, run through; I cleave through
5	Proto-Hellenic	*péryō	—