Zero-click search describes queries resolved on the search or AI surface itself, so no visit to a source site occurs. Featured snippets and knowledge panels started the trend; AI Overviews and AI assistants have accelerated it, since a synthesized answer often removes the need to click at all.
The strategic implication is that being cited or named inside the answer becomes more valuable than a ranking that never earns a click. It also means click-based metrics understate your influence, which is why AI share of voice and citation tracking matter alongside traffic.