Reappearance is the name of the event: the fact that someone or something is seen again after a time away. “His reappearance” means he is back in view. The doing word is reappear; this one names the coming-back itself. You meet it in news and in talk about film, sport, and health: a star’s reappearance on stage, the reappearance of a sickness. It feels a little more careful and paper-like than “when she showed up again.” Though actually, people reach for the noun when the return is the story they want to point at. If you only need to say what happened, the verb is often enough.

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