unavailable

Compared meaning: no longer existing or not obtainable (adjective).

比较义项：不再存在／无法获得（adj.）。

• gone

  Informal and blunt; implies something has disappeared, been used up, or a person has left, with no reason given; common with food, money, or people leaving a place.

  语气非正式且直接；暗示某物已经消失、用完，或某人已经离开，且不说明原因；常用于食物、金钱或人离开某地的情况。

  I checked the fridge, but the milk was already gone.

  我看了看冰箱，发现牛奶已经没了。

• unavailable 本词

  More formal and neutral; focuses on something currently not obtainable, accessible, or reachable, without suggesting it disappeared or was used up.

  语气更正式、更中性；强调某物目前无法获得、无法使用或联系不到，并不暗示它已经消失或被用完。

  The doctor is unavailable until next Monday.

  医生要到下周一才有空。

Gone and unavailable both describe something you cannot get, especially when sold out. Gone is informal, meaning something has disappeared or been used up. Unavailable is more formal, meaning something cannot currently be obtained or reached. Not compared: gone meaning someone has died.

这两个词都可以用来说“东西没了、拿不到了”，尤其是售罄这类语境；但gone语气更口语直接，强调东西已经消失或用完，unavailable更正式中性，强调目前无法获取、使用或联系上，并不暗示东西已经不在了。这里不比较gone表示“（委婉说法）已故、去世”的意思。