一头热

一头热:

Literally means:

only one side is hot

Actually means:

This phrase refers to unrequited enthusiasm or passion.

It means that in doing something which requires the participation of two sides or many sides, only one side is full of enthusiasm and passion while the other sides are indifferent and irresponsive which often leads to a failure. It is slightly derogative.

指只有单方面的热情或积极性。

表示做一件事需要双方或多方参与，只是一方充满热情，干劲十足，而其他方面却没有热情，不积极响应，事情往往是做不好的。略含贬义。