Having reason or the faculty of reasoning; endowed with reason; opposed to irrational; as, man is a rational being; brutes are not rational animals. It is our glory and happiness to have a rational nature.

Agreeable to reason; opposed to absurd; as a rational conclusion or inference; rational conduct.

Agreeable to reason; not extravagant.

Acting in conformity to reason; wise; judicious; as a rational man.

A rational being.