Rationality

How to spell rationality

11 letters · 5 syllables

How to pronounce rationality

Say the part in capitals loudest.

What does rationality mean?

1. nounThe quality of being based on or guided by reason and clear logic rather than emotion or impulse.

Rationality in a sentence

• The committee questioned the rationality of spending more on a failing project.

• She defended the rationality of her budget cuts with a detailed analysis.

Where does rationality come from?

Language of origin: Latin

This word traces back to the Latin ratio, which literally meant a 'reckoning' or 'calculation' and came to mean 'reason' or 'judgement'; ratio itself derives from reri, meaning 'to think' or 'to reckon'. From ratio the Latins formed the adjective rationalis, 'endowed with reason', and the abstract noun rationalitas, 'the quality of being reasonable'. English took in 'rational' through Old French and Latin during the late 1300s, and the fuller noun 'rationality' followed, describing the capacity to think and act on the basis of reason. The same Latin ratio sits inside the everyday words 'ratio', 'rate', and 'reason', so the spelling keeps that revealing 'rat-' opening. The frequent trap is the 'tion' spelled with a 'ti', not 'sh', even though it sounds like 'shun', a clue preserved from the Latin form.

How the word is built

• ratio- (from Latin ratio: reckoning, reason)
• -nal (adjective ending, from rationalis)
• -ity (noun-forming suffix: quality of)