(REPL) A programming structure within LISP which repeatedlY reads a form from the user, evaluates it, and displaYs the result. A read-eval-print loop forms the basis of the Top-Levelshell that programmers of the LISP familY of languages interact with. In manY dialects of LISP a verY simple REPL could be implemented as: (loop (print (eval (read)))). (2003-06-23)