rational
RASH-nuhl
Rational (adj) means Based on clear reasoning and logic rather than emotion. Example: “A rational person would check the facts before sharing a rumour.”
adj
1
Based on clear reasoning and logic rather than emotion.
"A rational person would check the facts before sharing a rumour."
"Try to make a rational decision instead of an impulsive one."
"His argument was calm and rational."
2
In mathematics, describing a number that can be written as a fraction of two whole numbers.
"Any whole number is a rational number because it can be written over one."
"The square root of two is not a rational number."
"3/4 is a rational number, but pi is not."
How to use rational
Learner’s notesIn plain EnglishSensible and logical, or (in math) expressible as a fraction.
Easily confused with
Common pairings
rational thought
rational number
rational decision
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Word forms
- Plural
- rationals
- Comparative
- more rational
- Superlative
- most rational
Fill the gap
Can you complete this real example?
A _____ person would check the facts before sharing a rumour.
Etymology
From Latin rationalis, "of reason," from ratio, "reason, calculation."
Synonyms
View more →Antonyms
Related words
Rhymes for rational
coronal
diagonal
personal
seasonal
national
optional
regional
hormonal
hexagonal
fictional
emotional
irrational
See all rhymes for rational →
Frequently asked questions
What does “rational” mean?
The word “rational” means based on clear reasoning and logic rather than emotion. In plain terms, sensible and logical, or (in math) expressible as a fraction.
How do you pronounce “rational”?
“Rational” is pronounced RASH-nuhl (/ˈɹæʃ(ə)nəl/ in IPA).
How do you use “rational” in a sentence?
Here is “rational” used in a sentence: “Try to make a rational decision instead of an impulsive one.”
What is the opposite of “rational”?
The opposite of “rational” — its antonyms — are absurd, irrational, nonsensical, arbitrary and arational.
What part of speech is “rational”?
“Rational” is an adjective.
Where does the word “rational” come from?
The word “rational” comes from Latin. From Latin rationalis, "of reason," from ratio, "reason, calculation.".
Is “rational” a common word?
“Rational” is a fairly common word in modern English, usually learned at around the B1 level.
How many meanings does “rational” have?
“Rational” has 2 distinct senses listed in this dictionary. The most common is: based on clear reasoning and logic rather than emotion.
What is the difference between rational and reasonable?
Rational emphasizes that something is based on clear reasoning and logic rather than emotion, as in "a rational decision." Reasonable emphasizes fairness and moderation, as in "a reasonable price" or "a reasonable request." A rational argument is logically sound; a reasonable one is fair and sensible.
What is the difference between rational and rationale?
Rational is an adjective meaning based on logic rather than emotion, while rationale is a noun meaning the set of reasons or logical basis behind a decision. You might explain the rationale for a plan and hope your audience finds it rational. The two are often confused because they look and sound similar.
What makes a number rational in mathematics?
In mathematics, a rational number is any number that can be written as a fraction of two whole numbers, such as 1/2, 3 (which equals 3/1), or 0.75 (which equals 3/4). Numbers that cannot be written this way, such as pi or the square root of 2, are called irrational numbers.
What is the opposite of rational?
The most direct opposite of rational is irrational, meaning not based on clear reasoning or logic. Depending on context, illogical, absurd, or arbitrary can also serve as opposites. In mathematics, irrational specifically describes a number that cannot be expressed as a fraction of two whole numbers.
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