'Thing' originally meant 'assembly, parliament' — preserved in Iceland's Althing. It broadened to mean anything.
An object, entity, or matter that is not or cannot be specifically named; any inanimate material object as distinct from a living being.
From Old English 'þing,' meaning 'assembly, council, meeting,' from Proto-Germanic *þingą (assembly, judicial gathering). The original meaning was a public meeting to discuss and settle affairs — the same word survives in the Icelandic Alþingi (Althing), the world's oldest surviving parliament, founded in 930 CE. The semantic shift from 'assembly' to 'matter discussed at assembly' to 'matter, affair' to 'any entity whatsoever' occurred gradually across the Germanic languages during the medieval period. Key roots: *þingą (Proto-Germanic: "assembly, judicial gathering"), *tenk- (Proto-Indo-European: "to think, to feel (possibly related)").
The most generic word in English for 'any object whatsoever' originally meant 'parliament.' The Icelandic Althing (Alþingi), founded in 930 CE and still operating today, preserves the original meaning — making 'thing' a word that traveled from 'legislative assembly' to 'that whatchamacallit on the table.'