gistfile1.js

var key, Hash, val;
 
Hash =
  {
  dog: "犬",
  cat: "猫",
  elefant: "象",
  pig: "豚",
  bird: "鳥",
};
 
//↓更新
Hash.elefant = "ぞう";
//↓こちらも可
//Hash["elefant"] = "ぞう";
 
for (key in Hash) {
  val = Hash[key];
  console.log("key -> " + key + ", val -> " + val);
}