Lukewarm (adjective)

1. Neither hot nor cold, especially in a way that is unenthusiastic or unresponsive.
2. Having or showing little enthusiasm.

Origin:

Late middle english: from luke, the patron saint of physicians, + warm (probably from the belief that his body temperature was higher than that of other saints).

Examples:

1. The response to the proposal was lukewarm.
2. The soup was lukewarm, so I asked for it to be heated up.
3. He was lukewarm about the idea of moving to a new city.
4. The reception was lukewarm and no one seemed very excited.
5. Her attitude towards the project was lukewarm and unenthusiastic.