Invulnerability is the state of not being able to be hurt. If someone or something has invulnerability, attack, damage, or even sharp criticism does not get through. Superheroes in stories are often given invulnerability: swords and bullets do not mark them. In real talk we use it more as an idea than a fact — a company may seem to enjoy invulnerability to scandal, or a public figure may wear an air of invulnerability. Though actually, we often use the word to doubt the claim: “the myth of their invulnerability” means they looked untouchable, until they were not. It is a formal, abstract noun; in daily speech people more often say “you can’t hurt them.”

刀槍不入；無懈可擊（指不會被傷害或被罵倒的狀態，不是遊戲裡的「無敵」）