In early Germanic society, an assembly of the free people of a community, presided over by lawspeakers, was known (prosaically enough) as a 'thing'. Such an assembly of the household retainers of a king, earl or chief was known as a 'house thing' – contrasted with the folkmoot, which is an Old English word for an assembly of the whole people. 'House thing' evolved into 'husting' – a word that was used to refer to the courts of the City of London, held before the Lord Mayor, the sheriffs and aldermen, for the purpose of hearing pleas of land, common pleas and appeals from the sheriffs.
The Tynwald, the parliament of the Isle of Man, is so called because it's the place where the thing met.
© Haydn Thompson 2019