如何删除数组中的重复单词？

function removeDuplicates(words) {
  var uniqueWords = [];
  
  for (var i = 0; i < words.length; i++) {
    if (uniqueWords.indexOf(words[i]) === -1) {
      uniqueWords.push(words[i]);
    }
  }
  
  return uniqueWords;
}

var wordsArray = ["apple", "banana", "apple", "orange", "banana", "grape"];
var uniqueWordsArray = removeDuplicates(wordsArray);
console.log(uniqueWordsArray);