Mammoth Uncensored Word List:
40 words ending with rn, 6 letters long

aldern altern astern attorn auburn bicorn casern cavern cedarn cohorn decern dehorn extern govern inborn intern inturn inworn lucern luzern modern reborn reearn retorn return rewarn reworn secern shairn suborn tavern unborn undern untorn unturn unworn uptorn upturn wivern wyvern