Argentine (adj.)

"of or from Argentina," 1830 (from 1829 as a noun, "citizen or inhabitant of the Argentine Republic"); Argentinian is from 1845 as a noun, 1858 as an adjective.

argentine (adj.)

mid-15c., "silver-colored;" c. 1500, "of or resembling silver," from Old French argentin (12c.), from Latin argentinus "of silver," from argentum "silver," from PIE root *arg- "to shine; white," hence "silver" as the shining or white metal.