intermediate

/ˌɪnərˈmidiɪt/

a substance formed during a chemical process before the desired product is obtained

中文释义：中间体；中间物

The chemical reaction produces an unstable intermediate.

化学反应产生一种不稳定的中间体。

The intermediate in the synthesis must be purified before further use.

合成中的中间体在进一步使用前必须纯化。