Since it is an agglutinative language, you can form longer and longer words by judiciously combining suffixes in Turkish: one such word that still makes perfect sense is proposed to be the longest Turkish word:
Muvaffakiyetsizleştiricileştiriveremeyebileceklerimizdenmişsinizcesine
For more details, see https://en.wikipedia.org/wiki/Longest_word_in_Turkish