Here are some synonyms for "self-evident":
* Obvious
* Clear
* Plain
* Apparent
* Understandable
* Unmistakable
* Incontrovertible
Examples:
* "It is self-evident that the earth is round." (This fact is widely accepted and doesn't require any complicated explanation.)
* "The need for clean water is self-evident." (It's clear that everyone needs clean water to survive.)
* "The benefits of exercise are self-evident." (It's easy to understand why exercise is good for your health.)
The term "self-evident" is often used in philosophical and legal contexts, particularly when referring to fundamental truths or principles. For example, the US Declaration of Independence famously states that "We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness."