Redux: brought back, resurgent (Wikipedia free dictionary). This essay traces the history of the concepts that led to the usage of the term 'nephrotic syndrome' beginning ∼90 years ago. We then examined the various definitions used for this syndrome and modified them to conform to contemporary standards. Remarkably, only minor modifications were required. This analysis of a common clinical entity may be helpful in ensuring appropriate evaluation of patients suffering from nephrotic syndrome and nephrotic-range proteinuria.