rationale

American  

[rash-uh-nal] / ˌræʃ əˈnæl /

noun

1. the fundamental reason or reasons serving to account for something.

   Synonyms:

   ground, basis, logic

2. a statement of reasons.

3. a reasoned exposition of principles.

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rationale British  

/ ˌræʃəˈnɑːl /

noun

1. a reasoned exposition, esp one defining the fundamental reasons for a course of action, belief, etc

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Etymology

Origin of rationale

First recorded in 1650–60; from Latin: neuter of ratiōnālis rational

Explanation

The rationale for something is the basic or underlying reason or explanation for it. This noun (pronounced "rash-uh-NAL") is usually used in the singular: What was the rationale behind his decision to quit? The related adjective rational means "based on facts or reason" or "having the ability to think clearly." An example of a rational rationale? You add extra baking soda to pancake batter under the rationale that if you want them to be fluffier, you need more rising agent. Rationale is from Latin, from rationalis "relating to reason," from ratio "calculation, reason," from rērī "to consider, think."

Example Sentences

If launch costs don’t get cheaper, to highlight one example, the business rationale for orbital data centers becomes harder to make.

From The Wall Street Journal • May 12, 2026

Her rationale is that it puts brands back in the driver’s seat.

From Barron's • May 12, 2026

The rationale was that if the central midfielders focused on Silva, the attacking midfielders would have space.

From BBC • May 4, 2026

This is the rationale behind the downgrade to neutral.

From MarketWatch • Apr. 29, 2026

The other rationale is that Toni Morrison’s is an adjective, and pronouns must refer back to nouns.

From "The Sense of Style" by Steven Pinker

Related Words

• excuse
• explanation
• hypothesis
• justification
• motivation
• motive
• philosophy
• principle
• rationalization
• reason
• theory