Rational
Part of speech: adjective
Definition: Reasonable; not absurd, foolish, emotional, or fanciful. Capable of reasoning. Of a number, capable of being expressed as the ratio of two integers. Of an algebraic expression, capable of being expressed as the ratio of two polynomials.
Part of speech: noun
Definition: A rational number: a number that can be expressed as the quotient of two integers.
Example sentence: No rational argument will have a rational effect on a man who does not want to adopt a rational attitude.
Intellectual
Part of speech: adjective
Definition: Belonging to, or performed by, the intellect; mental; as, intellectual powers, activities, etc.Endowed with intellect; having the power of understanding; having capacity for the higher forms of knowledge or thought; characterized by intelligence or mental capacity; as, an intellectual person.Suitable for exercising the intellect; formed by, and existing for, the intellect alone; perceived by the intellect; as, intellectual employments.Relating to the understanding; treating of the mind; as, intellectual philosophy, sometimes called "mental" philosophy.
Part of speech: noun
Definition: An intelligent person, someone interested in intellectual matters.The intellect or understanding; mental powers or faculties.
Example sentence: My definition of an intellectual is someone who can listen to the William Tell Overture without thinking of the Lone Ranger.