General Science


  • noun a procedure in which a membrane is used as a filter to separate soluble waste substances from the blood

Origin & History of “dialysis”

As in the case of its close relative analysis, the underlying etymological notion contained in dialysis is of undoing or loosening, so that the component parts are separated. The word comes ultimately from Greek diálusis, a derivative of dialúein ‘tear apart’; this was a compound verb formed from the prefix dia- ‘apart’ and lúein ‘loosen, free’ (related to English less, loose, lose, and loss). In Greek it meant simply ‘separation’, but it was borrowed into English, via Latin dialysis, as a rhetorical term denoting a set of propositions without a connecting conjunction. The chemical sense, ‘separation of molecules or particles’ (from which the modern application to ‘renal dialysis’ comes), was introduced in the 1860s by the chemist Thomas Graham (1805–1869).