irrational

/ɪˈræʃənəl/
adjective
  1. Not based on reason or clear thinking; illogical.
    • Her fear of spiders was so irrational that she refused to enter any room without checking the corners first.
    • The manager made an irrational decision to fire the entire team without any evidence of wrongdoing.
    • It is irrational to believe that wearing a certain color will bring you good luck.
  2. In mathematics, describing a number that cannot be expressed as a simple fraction of two integers.
    • The square root of 2 is an irrational number because its decimal never repeats or ends.
    • Students learn that irrational numbers like e appear frequently in advanced mathematics.
    • Pi is one of the most famous irrational numbers, used in calculations involving circles.
noun
  1. An irrational number.
    • Many irrationals, such as √3, are important in geometry.
    • In algebra class, we learned how to identify rationals and irrationals on a number line.
    • The teacher explained that the decimal expansion of an irrational never terminates.
What does "irrational" mean? | whatsthatwordmean | whatsthatwordmean