If you count by total lines of code running in production, then the most likely winner is probably C or COBOL (decent chance your paycheck relies on large COBOL applications working correctly). If you count it by lines of code times number of running instances, then I'm really hard-pressed to pick any other language of C because of its sheer prevalence in things such as cars. If you count by number of programmers, I'm not sure what the winner ends up being.
Even crufty old languages like FORTRAN or COBOL have surprisingly wide usage. Sure, they may be completely absent in user-facing applications, but it's easy to forget that such applications are only a small portion of applications. JS itself would probably end up somewhere in the bottom half of the top 10 in most metrics of "top languages," as it has very little presence outside of user-facing applications.