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

Even the tariff against India, imposed in late August, was limited in scope and uneven in rationale. —Brett Erickson, MSNBC Newsweek, 4 Sep. 2025

After posting the question, the LLM provided an answer and the rationale behind it. —Bernardo Martinez, Forbes.com, 3 Sep. 2025

The main rationale for waiting is potential price effects from tariffs, but that concern is overstated. —Phillip Molnar, San Diego Union-Tribune, 29 Aug. 2025

Quite simply, Naomi and her sister, Mari, have always felt Japanese, so that was our only rationale. —Jacklyn Krol, People.com, 26 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