fluxion

/ˈflʌkʃən/
noun
  1. A continuous change or flow; the process of flowing or changing.
    • The fluxion of the river carved new paths through the valley over centuries.
    • In physics class, we studied the fluxion of heat through different materials.
    • The artist captured the fluxion of light and shadow in her painting.
  2. In mathematics (historical), the rate of change of a variable; an early term for derivative in calculus.
    • The student struggled to understand the concept of fluxion in the history of calculus.
    • The textbook explained that a fluxion measures how quickly a quantity changes over time.
    • Newton used the term fluxion to describe what we now call the derivative of a function.
Synonyms