title: Is my understanding of a reducible expression i.e. redex correct?
body: <p>Programming in Haskell by Hutton says:</p>
  
  <blockquote>
    <p>An expression that has the form of a function applied to  one or  more arguments that can be ‘reduced’ by performing  the application is called a reducible expression,   or redex for short. </p>
  </blockquote>
  
  <p>Is a reducible expression i.e. redex exactly </p>
  
  <ul>
  <li><p>a function application where the function is not the result of another function application, </p></li>
  <li><p>equivalently, a function application where the function is either a function name or a lambda expression?</p></li>
  </ul>
  
  <p>Is either of the above two points an answer to my previous question at <a href="https://stackoverflow.com/questions/57023894/how-does-the-outermost-evaluation-strategy-evaluate-partial-application-of-a-fun">How does the outermost evaluation strategy evaluate partial application of a function and application of a curried function</a>?</p>