Meaning of the word rationale in English

What does rationale mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

rationale

US /ˌræʃ.əˈnæl/
UK /ˌræʃ.əˈnɑːl/
"rationale" picture

Noun

the fundamental reason or reasons serving to account for something

Example:
The rationale for the new policy was explained in detail.
What is the rationale behind your decision?