Zyzzogeton is a rare genus of leafhopper endemic to South America. It is named after a former genus Zyzza (probably an onomatopoeia), appended with the ancient Greek geitōn (γείτων ‘neighbour’). The word is known for being the last word defined in the Webster's New International Dictionary, Unabridged released in September 1961. It also appears in the 1939 Second edition, and is still present in current versions.