Meaning & Definition of word "Irrational"
to
Irrational
/ɪˈræʃ.ən.əl/
adjective:
- 1. Not based on reason or logic; unreasonable.
- Example: His decision to quit his job without another offer was seen as irrational by his colleagues.
- 2. In mathematics, not expressible as a ratio of two integers.
- Example: The square root of 2 is an irrational number because it cannot be represented as a fraction.
Etymology
From the Latin 'irrationalis', from 'in-' (not) + 'rationalis' (rational).
Common Phrases and Expressions
irrational exuberance:
A term used to describe overly enthusiastic behavior in investors.
Related Words
rational:
Based on or in accordance with reason or logic.
reason:
The power of the mind to think, understand, and form judgments logically.
logical:
Of or according to the rules of logic or formal argument.
Slang Meanings of irrational
Meaning: Crazy
Example Sentence: That idea is totally irrational, it's crazy!
Meaning: Out of one's mind
Example Sentence: He must be out of his mind to think that's a good plan!