How to use a string as a variable name in Javascript? [duplicate]

Stop. Reorganise your code. If you want to select variables with a variable, then there has to be a logical grouping for them. Make it explicit.

var chat = {
    "1": "one",
    "2": "two"
};
var id = 1;
var new_is_a_keyword_and_cant_be_an_identifier = chat[id];