Titin: derived from the Greek titan (a giant deity, anything of
great size). This is a fitting name considering its name.
Because it is the largest known protein it also has the longest
IUPAC name which starts with “methiony...” and ends with
“...isoleucine” and contains about 1.5 thousand letters in
between. This makes it the longest word in not only the English
language but also in any other language on Earth. Titin is very
important in the contraction of muscle tissue. Only a few
lexicographers accept chemical formulae as words, even if the
chemical makes it possible for them to write words. As a result
you won’t find the word in most dictionaries. But hey, Google
doesn’t seem to mind it, and so it’s still considered by many to
be the longest word.