PUZZLE: English into French

My Editor-in-Chief at Games, Wayne Schmittberger, sent me this puzzle from Martin Gardner's final, posthumously-published Colossal Book of Word Play (Puzzlewright, $8.95).

What English word when spelled backward becomes its own French plural (i.e., the plural of itself translated into French)?

Answer: STATE (ETATS) [ignoring that etat has an accent aigu on the e]