half as much again

here is something that i love:

sesquipedalian

1615, from Latin sesquipedalia verba "words a foot-and-a-half long," in Horace's "Ars Poetica" (97), nicely illustrating the thing he is criticizing, from sesqui- "half as much again"

also (this is from wikipedia):

The longest word in any of the major English language dictionaries is pneumonoultramicroscopicsilicovolcanoconiosis, a 45-letter word that refers to a lung disease contracted from the inhalation of fine silica dust. Research has discovered that this word was originally intended as a hoax. It has since been used in a close approximation of its originally intended meaning, lending at least some degree of validity to its claim.

The Oxford English Dictionary contains pseudopseudohypoparathyroidism (30 letters).

The longest non-technical word in major dictionaries is flocci­nauci­nihili­pili­fication at 29 letters. Consisting of a series of Latin words meaning "nothing" and defined as "the act of estimating something as worthless," its usage has been recorded as far back as 1741. In recent times its usage has been recorded in the proceedings of the United States Senate by Senator Robert Byrd, and at the White House by Bill Clinton's press secretary Mike McCurry, albeit sarcastically.

albeit.