1. 通情达理的;头脑清醒的;情绪稳定的
If you describe someone as well-balanced, you mean that they are sensible and do not have many emotional problems.

2. 均衡的;均匀的
If you describe something that is made up of several parts as well-balanced, you mean that the way that the different parts are put together is good, because there is not too much or too little of any one part.

1. free from psychological disorder

e.g. a well-adjusted personality

Synonym: well-adjusted

2. in an optimal state of balance or equilibrium

e.g. a well-balanced wheel