Kokko, kokoo kokoon koko kokko. Koko kokkoko? Koko kokko!
"Eagle [pn.], collect together the whole bonfire. The whole bonfire? Yes, the whole bonfire!"
– Finnish uh, folk meme saying with almost just one consonant and also just one vowel
Sanskrit has an extreme form of citrakāvya (picture-poetry) called ekākṣarā (one-syllable/one-letter). The name speaks pretty much for itself. Here is a famous example from Bhāravi: