An adjective, A word from the Walt Disney film production of Mary Poppins, in 1964, describing any quality that is so wonderful, and so indescribable that you have no other word to say it with!
Here are the lyrics--- "It's Supercalafragilisticexpialidocious, Even though the sound of it is something quite atrocious If you say it loud enough you'll always sound precocious, supercalifragilisticexpialidocious!" (hopefully this is right- remembering is getting harder and harder since 1964. )
its a ridiculously long word made of pre- and suffixes that means:
su?per?cal?i?frag?i?lis?tic?ex?pi?al?i?do?cious [soo-per-kal-uh-fraj-uh-lis-tik-ek-spee-al-i-doh-shuhs] adjective (used as a nonsense word by children to express approval or to represent the longest word in English.)
Spaajir and AustinLinda both have the right of it and it's the most quoted non-word that never quite made it into the language. It even gave rise to the most famous sporting headline in newspaper history.
About 10 years ago in the Scottish FA Cup, the underdogs, "Inverness Caledonian Thistle" whose fans abbreviate their name to "Cally" defeated the mighty Celtic United team.
The next day's headline read, "Super Cally go ballistic, Celtic are atrocious."