The word "in-sane" denotes that something is irrational or mentally deranged. Some antonyms to "in-sane" include "sane," "mentally stable," "rational," and "sensible." "Sane" implies being mentally healthy and having a sound mind, while "mentally stable" indicates the ability to control one's thoughts and emotions in a rational manner. "Rational" describes a process of reasoning that is logical and reasonable, while "sensible" refers to an intelligent and prudent decision. These antonyms signify the opposite of "in-sane" and are commonly used to describe individuals who possess a balanced and healthy mind.