Thesaurus

Synonyms for Irrational include:

absurd, amok, amuck, around the bend, balmy, barmy, bats, batty, berserk, blind, bonkers, brainsick, buggy, certifiable, certified, confused, counterintuitive, crackbrained, cracked, crackers, crazed, crazy, daft, demented, demoniac, demoniacal, deranged, disconnected, disjointed, disordered, distracted, disturbed, dotty, fey, fruity, fuzzy, garbled, half-crazed, haywire, hebephrenic, idiotic, illogical, immoderate, incoherent, inconsequential, indefensible, insane, intuitive, irrational, kookie, kooky, loco, loony, loopy, lunatic, mad, magnitude relation, maniac, maniacal, manic-depressive, maniclike, mentally ill, mindless, moonstruck, non compos mentis, nonrational, nuts, nutty, of unsound mind, paranoid, possessed, psychopathic, psychopathologic, psychopathological, psychotic, quantitative relation, raving, raving mad, reasonless, round the bend, scattered, schizophrenic, screw-loose, screwy, senseless, sick, superstitious, touched, unbalanced, unconnected, undue, unhinged, unjustified, unlogical, unreasonable, unreasoning, unsound, unstable, untenable, unwarranted, visceral, wacky, whacky, wild

irrational is a ADJ.

irrational, irrational number

irrational is a NOUN.