rationale

noun

ra·​tio·​nale ˌra-shə-ˈnal 

1

: an explanation of controlling principles of opinion, belief, practice, or phenomena

2

: an underlying reason : basis

Did you know?

Rationale comes from Latin ratio, meaning "reason," and rationalis, "endowed with reason." Ratio is reasonably familiar as an English word for the relationship (in number, quantity, or degree) between things.

Synonyms

• explanation
• reason
• argument

Examples of rationale in a Sentence

the rationale for starting the school day an hour later is that kids will supposedly get an extra hour of sleep

Recent Examples on the Web

If revenue growth begins to slow, the rationale for the company’s elevated valuation may weaken. —Trefis Team, Forbes.com, 8 Aug. 2025

This rationale enabled Marines to pursue Sandinistas with impunity, leading to allegations of civilian targeting, village razing, and indiscriminate airplane bombing. —Time, 8 Aug. 2025

The rationale is that top players will then be available to appear in the mixed doubles, attracting more fans and allowing broadcasters to spotlight the competition before main draw singles play begins. —George Ramsay, CNN Money, 7 Aug. 2025

Emerging new players in space, like other countries, commercial interests and nongovernmental organizations, may have other goals and rationales. —Tony Milligan, Space.com, 3 Aug. 2025

Word History

Etymology

Latin, neuter of rationalis

First Known Use

1657, in the meaning defined at sense 1

Rhymes for rationale

• chaparral
• ileal
• musicale
• perceval
• supernal
• bal
• dal
• gal
• mal
• pal
• sal
• shall

Kids Definition

rationale

noun

ra·​tio·​nale ˌrash-ə-ˈnal 

: a basic reason or explanation for something