I think it's pretty clear that JavaScript is the most popular one. And yes, it's popular because in it's space it's without alternatives. But so was C for many environments. We can judge if that's fair or unfair, but it does not change the situation we have.
Dictionary.com:
1. regarded with favor, approval, or affection by people in general
2. regarded with favor, approval, or affection by an acquaintance or acquaintances:
3. of, relating to, or representing the people, especially the common people:
4. of the people as a whole, especially of all citizens of a nation or state qualified to participate in an election:
5. prevailing among the people generally:
6. suited to or intended for the general masses of people:
7. adapted to the ordinary intelligence or taste:
8. suited to the means of ordinary people; not expensive:
I have always associated popular with definition 1. Let me ask differently: do people really like JavaScript or they like web and JavaScript is forced upon them since there are no alternatives (and they actually dislike/hate it)?