Plenteous
Origin
From Middle English, circa 1300, from Old French plentiveus ("fertile, rich") (early 13th century), from plentif ("abundant"), from plenté ("abundance")
Online Etymology Dictionary
(Modern French pleinté, English plenty), from Latin plenitatem, accusative of plenitas ("fullness"), from plenus ("complete, full"), from Proto-Indo-European *plÌ¥hâ‚nós ("full").