The word is a compound word, and said by Richard Lederer in his book Crazy English to be made up of these words: super- “above”, cali- “beauty”, fragilistic- “delicate”, expiali- “to atone”, and -docious “educable”, with all of these parts combined meaning “Atoning for being educable through delicate beauty.

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It’s not the longest word in the English language—according to most dictionaries, that honor belongs to the 45-letter medical term “pneumonoultramicroscopicsilicovolcanoconiosis.” But ask anyone on the street and they will likely offer up the easily remembered “supercalifragilisticexpialidocious” (34 letters) as the top contender for polysyllabic grand-champion.

Why is “supercali” so memorable? THE SONG, of course! Years before the popularization of “self-talk” as part of the Personal Growth movement, Mary Poppins knew how to get her head straight—just sing the catchy little tune!

Penned by songwriting brothers Robert B. and Richard M. Sherman, who wrote a number of now-famous songs for Walt Disney productions (The Jungle Book, Chitty Chitty Bang Bang, The Many Adventures of Winnie the Pooh, and It’s a Small World—one of the most translated and performed songs ever written!), Julie Andrews brought “Supercali” to life as Mary Poppins in the 1964 Disney film by the same name.

The Sherman brothers won an Academy Award in 1965 for “Chim Chim Cher-ee,” also from Mary Poppins, and topped the pop charts in 1974 when ex-Fab Four Ringo Star’s cover of their song “You’re Sixteen” reached #1. (“You’re Sixteen” was previously made a top-ten hit in 1960 by rockabilly singer Johnny Burnette.)

The Sherman brothers came naturally to their songwriting prowess, being the sons of Al Sherman, a noted Tin Pan Alley tunesmith.

Supercalifragilisticexpialidocious Lyrics
(Words and Music by Robert B. and Richard M. Sherman)

Um diddle diddle diddle um diddle ay
Um diddle diddle diddle um diddle ay

Supercalifragilisticexpialidocious!
Even though the sound of it
Is something quite atrocious
If you say it loud enough
You’ll always sound precocious
Supercalifragilisticexpialidocious!

Um diddle diddle diddle um diddle ay
Um diddle diddle diddle um diddle ay

Because I was afraid to speak
When I was just a lad
My father gave me nose a tweak
And told me I was bad
But then one day I learned a word
That saved me aching nose
The biggest word I ever heard
And this is how it goes:

Oh, supercalifragilisticexpialidocious!
Even though the sound of it
Is something quite atrocious
If you say it loud enough
You’ll always sound precocious
Supercalifragilisticexpialidocious!

Um diddle diddle diddle um diddle ay
Um diddle diddle diddle um diddle ay

So when the cat has got your tongue
There’s no need for dismay
Just summon up this word
And then you’ve got a lot to say
But better use it carefully
Or it may change your life
One night I said it to me girl
And now me girl’s my wife!

She’s supercalifragilisticexpialidocious!
Supercalifragilisticexpialidocious!
Supercalifragilisticexpialidocious!

Supercalifragilisticexpialidocious!