rational
/ˈræʃənəl/adjective
1
- based on or in accordance with reason or logic基于理性的, 合理的; 基于逻辑的, 合乎逻辑的：
I'm sure there's a perfectly rational explanation.
我确信有完全合理的解释。
1.1
- (of a person) able to think clearly, sensibly, and logically（人）理性的, 理智的; 明事理的：
Ursula's upset - she's not being very rational.
厄休拉烦躁不安——她现在不太理智。
1.2
- endowed with the capacity to reason富有理性的：
man is a rational being.
人是理性动物。
2
- Mathematics (of a number, quantity, or expression) expressible, or containing quantities which are expressible, as a ratio of whole numbers. When expressed as a decimal, a rational number has a finite or recurring expansion.【数】有理的; 有理数的。
派生词
rationality
nounrationally
adverb词源
late Middle English （in the sense 'having the ability to reason'）： from Latin rationalis, from ratio（n-） 'reckoning, reason' （see RATIO）.