Lots of stack-machine languages are based on Reverse Polish Notation, including Forth, MSIL, HP's RPN. But there's nothing reverse about Lisp.
@Proton2: before IDEs started providing substantial help with that, it was common to use a "final square bracket" that closed any open parenthesis left.
(cons a (cons b (cons (c nil)]
Slightly more dangerous than a having a live piranha in your pocket, but it was a life saver.