noun · a figurative means used to conceal oneself or hide one's true motives or plans

他竟然想把这个虚假的理由当做逃避责任的隐身草。

noun · legendary grass that is said to make the person holding or wearing it invisible

在古代神话中，主人公正是靠着一株隐身草才逃出了妖怪的洞穴。