Definition of rationale
1 : an explanation of controlling principles of opinion, belief, practice, or phenomena
2 : an underlying reason : basis
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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
Did You Know?
The word rationale appeared in the second half of the 17th century, just in time for the Age of Reason. It is based on the Latin ratio, which means "reason," and rationalis, which means "endowed with reason." At first, rationale meant "an explanation of controlling principles" ("a rationale of religious practices," for example), but soon it began to refer to the underlying reason for something (as in "the rationale for her behavior"). The latter meaning is now the most common use of the term. The English word ratio can also mean "underlying reason" (in fact, it had this meaning before rationale did), but in current use, that word more often refers to the relationship (in number, quantity, or degree) between things.
Origin and Etymology of rationale
Latin, neuter of rationalis
First Known Use: 1657
RATIONALE Defined for English Language Learners
Definition of rationale for English Language Learners
: the reason or explanation for something
RATIONALE Defined for Kids
Definition of rationale for Students
: a basic explanation or reason for something What is the rationale behind your decision?
Seen and Heard
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