rational Definition

rational
adj

1. Related to or based on reason or logic.

Thesaurus: intellectual, cognitive, mental, deductive, analytical.
2. Able to think, form opinions, make judgements, etc.
3. Sensible or reasonable.

Thesaurus: sensible, wise, judicious, logical, sagacious, realistic, knowing, lucid, coherent, sober, sane, balanced.
4. math.
Said of a quantity, ratio, root: able to be expressed as a ratio of whole numbers.

Derivative: rationality

Being rational.

The possession or due exercise of reason.

Reasonableness.

Derivative: rationally
adverb

Etymology: 14c: from Latin rationalis, from ratio reason.