Which term describes something that is irrational and absurd?

The term that best describes something that is irrational and absurd is "unreasonable." This word conveys a lack of sound judgment or reason, indicating that the idea or action in question does not conform to logical thinking or accepted standards of rational behavior. In contexts involving decision-making or actions, labeling something as unreasonable implies that it defies common sense or rational evaluation.

While terms like "logical," "rational," and "reasonable" imply sound judgment and adherence to logic and sensibility, they do not align with the meanings associated with irrationality and absurdity. Logical refers to something that follows a coherent reasoning structure, rational pertains to actions or thoughts that are based on reason rather than emotion, and reasonable suggests a justifiable approach that aligns with common sense. Each of these terms stands in contrast to the concept of being unreasonable, which captures that lack of rational thought or absurdity clearly.