The best way nowadays is to use the map() function in this way:

var resultArr = arr.map(function(x){return x.replace(/,/g, '');});

this is ECMA-262 standard. If you nee it for earlier version you can add this piece of code in your project:

if (!Array.prototype.map)
{
    Array.prototype.map = function(fun /*, thisp*/)
    {
        var len = this.length;
        if (typeof fun != "function")
          throw new TypeError();

        var res = new Array(len);
        var thisp = arguments[1];
        for (var i = 0; i < len; i++)
        {
            if (i in this)
                res[i] = fun.call(thisp, this[i], i, this);
        }

        return res;
    };
}

You can simply do:

array = ["erf,","erfeer,rf","erfer"];
array = array.map(function(x){ return x.replace(/,/g,"") });

Now Array Becomes:

["erf", "erfeerrf", "erfer"]

you can also do it inline in a shorter syntax

array = array.map(x => x.replace(/,/g,""));

Sure -- just iterate through the array and do a standard removal on each iteration.

Or if the nature of your array permits, you could first convert the array to a string, take out the commas, then convert back into an array.