Definition

The quality or state of not being reasonable or logical; acting without clear thinking or understanding.

Example

His decision was based on pure irrationality rather than facts.

Conversation

Have you ever noticed how people can act out of complete irrationality?

Yeah, it’s surprising what some folks will do without thinking.

Right? Sometimes I wonder what drives such irrationality in decision-making.

I guess emotions can really cloud judgment in those moments.

Synonyms & Antonyms

Root Explanation

Irrationality → It is formed from "ir-" (meaning not) and "rationalis" (from Latin, meaning reasonable or logical) and the suffix "-ity" (meaning the state or quality of). The word "irrationality" refers to the state of being not reasonable or lacking logic.

Memory Tip

Think of 'not' ('ir-') being combined with 'reasonable' ('rationalis') to remember that 'irrationality' means a lack of reason or logic.

Visually Confused Words