The word "skepticism" is a combination of "skeptic" and "ism". Skepticism means the belief or attitude of a person inclined to question or doubt all accepted opinions. To make this word by combining the base and suffix is pretty simple. Someone can be skeptic and the suffix -ism is what changes the action of being skeptic, to a noun, skepticism. The suffix actually adds the possession to the person and that helps it become the noun, skepticism. A sentence to help show how this noun is used is "His skepticism may have led him into errors of his own.".