Here's how you can think about it:
* Absurd: An adjective describing something that is illogical, unreasonable, or nonsensical.
* Absurdity: The state or quality of being absurd. It refers to the concept of something being illogical, unreasonable, or nonsensical.
For example:
* "The idea of talking cats is absurd." (adjective)
* "The absurdity of the situation was evident to everyone." (abstract noun)