Where does “paeninsula” come from?

paeninsula (Latin) comes from Latin paene, from Proto-Indo-European peh₁- — to hate, hurt.

Ancestry of “paeninsula”, step by step

Step	Language	Word	Meaning
1	Latin	paene	almost, nearly; scarcely, hardly, barely
2	Proto-Indo-European	peh₁-	to hate, hurt

paeninsula — Etymology, Origin & Word History | Etymology Explorer