sane

An sane person thinks clearly and behaves reasonably.

Being "sane" means being normal or mentally healthy. It's not about being perfect, but rather about having a good sense of reality and being able to cope with life's challenges. In everyday conversation, people often use this word to describe someone who is acting rationally and making smart decisions. For example, if your friend makes a silly investment decision, you might say, "That's not very sane, don't you think?" To be considered sane, someone usually needs to have their emotions under control and be able to understand what's going on around them.

It's worth noting that the word "sane" can also be used in more formal or medical contexts. In these cases, it's often used to describe someone who has been evaluated by a doctor or mental health professional and is considered to have a healthy mind.