| Adj. | 1. | rational - consistent with or based on or using reason; "rational behavior"; "a process of rational inference"; "rational thought"logical - capable of or reflecting the capability for correct and valid reasoning; "a logical mind" reasonable, sensible - showing reason or sound judgment; "a sensible choice"; "a sensible person" sane - mentally healthy; free from mental disorder; "appears to be completely sane" irrational - not consistent with or using reason; "irrational fears"; "irrational animals" | |
| 2. | rational - of or associated with or requiring the use of the mind; "intellectual problems"; "the triumph of the rational over the animal side of man"mental - involving the mind or an intellectual process; "mental images of happy times"; "mental calculations"; "in a terrible mental state"; "mental suffering"; "free from mental defects" | |
| 3. | rational - capable of being expressed as a quotient of integers; "rational numbers"math, mathematics, maths - a science (or group of related sciences) dealing with the logic of quantity and shape and arrangement irrational - real but not expressible as the quotient of two integers; "irrational numbers" | |
| 4. | rational - having its source in or being guided by the intellect (distinguished from experience or emotion); "a rational analysis"intellectual - appealing to or using the intellect; "satire is an intellectual weapon"; "intellectual workers engaged in creative literary or artistic or scientific labor"; "has tremendous intellectual sympathy for oppressed people"; "coldly intellectual"; "sort of the intellectual type"; "intellectual literature" | |