Whoa....I cry foul on that one. I can't believe something like alcohol which has been sold worldwide for millennia can be outsold by the rubiks cube? Maybe modern history... Too much social media

Thank you, first time ever to get 2 in a row! Maybe because I put up so many guesses, hope that is kosher.

It is a French word. Since I know it, I won't spoil everyone's fun except to say it is a word that can have several meanings. I will come back later to see if anyone else knows it. If not, I will answer the question. :-)

Oops, Fido means faithful or trustworthy from the Latin fidus or fidelis (If you are an opera or Beethoven fan, think also of "Fidelio"). We used to sing "O Come, All Ye Faithful" in Latin (Adeste Fidelis) in school. Having four years of Latin in high school helped, too. ;-)