Rational

How to spell rational

8 letters · 3 syllables

How to pronounce rational

Say the part in capitals loudest.

What does rational mean?

1. adjectiveBased on clear thinking and sound reasoning rather than emotion or impulse.
2. adjectiveOf a number that can be expressed as a ratio of two whole numbers.

Rational in a sentence

• A rational decision about the budget calmed the worried investors.

• The teacher explained that one half is a rational number.

• She stayed calm and rational even when the negotiations grew tense.

• Every terminating decimal is a rational value.

Where does rational come from?

Language of origin: Latin

This word comes from the Latin rationalis, meaning 'endowed with reason' or 'reasonable', which was built on the noun ratio. That noun originally meant a reckoning, a calculation, or an account, and only later widened to mean reason or judgement; it in turn came from the verb reri, 'to reckon' or 'to think'. English took the word in during the late 1300s, partly through Old French, and used it first to describe beings or thoughts governed by reason. The same ratio root sits inside a whole family of English words, including 'ratio', 'ration', 'reason' and 'rationale', which is exactly why the central syllable is spelled with -tion- even though it sounds like 'sh'. Keeping that hidden 'ratio' in mind is the surest way to remember the spelling.

How the word is built

• ration- (from Latin ratio: reckoning, reason)
• -al (adjective suffix)