JSFiddle - React, Tailwind, and code Playground

JavaScript

// creating regex
var words = ['bad', 'words'];
var wordsStr = "";
for(var i=0; i<words.length; i++) {
    wordsStr += words[i]; 
    if (i < words.length -1) {
        wordsStr += "|"; 
    }
}
var regex = new RegExp(wordsStr, "gi"); // g: replace all; i:insensitive

// replacing
var text = "I cant say bad words!";
text = text.replace(regex, "****");

alert(text);