the word 'thrift' originates from the old norse adjective 'þrifask', meaning 'to thrive or prosper'. it entered middle english as 'thrift', initially carrying the sense of 'prosperity, condition of thriving'. the semantic evolution is logical: the concept of thriving or prospering became closely associated with the means to achieve it—namely, the careful management and growth of one's resources. over time, the meaning narrowed from the general state of prosperity to the specific virtue of economical management that leads to such a state. this journey from a state of being to a practice enabling that state illustrates a classic metonymic shift in word meaning.

this word is a simplex form derived from a single old norse root.