We've found 5 phrases for irrational (0.178 seconds):

go ballistic »    To become very angry and irrational.

go batshit »    To become completely irrational; to react in an irrationally extreme manner.

have a screw loose »    A phrase meaning that the subject is insane or irrational.

off the deep end »    Crazy, erratic, or irrational.

scare out of one's wits »    To frighten someone to such an extent that they behave irrationally.

BTW, Why won't you become an editor?