Here's how it's broken down:
* お (o): This is an honorific prefix that adds politeness.
* 母 (ka): This means "mother".
* さん (san): This is a respectful suffix used after names or titles.
You can also use お母様 (okaasama), which is even more formal and respectful.
So, while "okaasan" is the most common way to say "mother" in Japanese, "okaasama" would be used in more formal settings or when addressing someone you are trying to show great respect to.