A language with 84 consonants and just two vowels died with one man in 1992

Ubykh, once spoken in the Caucasus, had an extraordinarily large consonant inventory, around 84 distinct consonant sounds by most counts, built from a tiny set of only two or three vowels, making it a favourite case study for linguists interested in the outer limits of possible sound systems. Its last fully fluent native speaker, Tevfik Esenç, worked for decades with linguists to record the language before his death in Turkey in 1992, after which Ubykh had no remaining native speakers.

— Georges Dumézil / Georges Charachidzé, The Ubykh Language — Fieldwork with Tevfik Esenç, 1950s–1980s