What is the X in X-mas?
"edible fungus," 1590s, from Middle French trufle (late 14c.), from Old French truffe, probably from Old Provençal trufa, metathesized from Late Latin tufera (plural), cognate of Latin tuber "edible root." Another theory notes Italian tartuffo (Milanese tartuffel) "potato," supposedly from terræ tuber. Extended 1926 to powdered, round chocolates that look like truffles.