I remember singing in school the song with the word Supercalifragilisticexpialidocious, from Mary Poppins. I also like the word from the title of a german children book: Der satanarchaeoluegenialkohoellische Wunschpunsch. It contains the words satan, anarch(y), archeo(logy), lie, brilliant, alcohol, hellish.
Is it Greek/Roman in origin or something else entirely.
It is related to the word zygote (and zygomatic, both of which are clearly of Greek origin), which is more commonly known as the last two word of the dictionary that finds common usage.
It's even related to another awesome word: syzygy! No yoke. /terribadpun
It also clearly contains a similar form to dogma, enigma, magma, stigma and the oh-so-Greek sigma and Zeus. The last one isn't actually related to zeugma (in a sense). So it most definitely looks like Greek.
