no rhyme or reason

no rhyme or reason

A total absence of a reasonable or rational explanation for something. I've looked over it several times, but there's no rhyme or reason to the agreement we were sent this morning.
See also: reason, rhyme

rhyme or reason, no

An absence of common sense or reasonableness, as in This memo has no rhyme or reason. Closely related variants are without rhyme or reason, as in The conclusion of her paper was without rhyme or reason, and neither rhyme nor reason, as in Neither rhyme nor reason will explain that lawyer's objections. This term originated in French about 1475 and began to be used in English about a century later. Sir Thomas More is credited with saying of a mediocre book that a friend had put into verse, "Now it is somewhat, for now it is rhyme; whereas before it was neither rhyme nor reason."
See also: rhyme

no rhyme or reason

or

no rhyme nor reason

If there is no rhyme or reason or no rhyme nor reason for something, there seems to be no logical or obvious explanation for it. There seems no rhyme or reason behind the pricing of many of these products. I can see no rhyme nor reason for the variance in spelling. Note: You can also say that something happens without rhyme or reason. Symptoms appear and disappear apparently without rhyme or reason. Cuts are being made without rhyme or reason. The only motive is to save money to meet Treasury targets.
See also: reason, rhyme
References in classic literature ?
Everyone had some defect, of body or of mind: he thought of all the people he had known (the whole world was like a sick-house, and there was no rhyme or reason in it), he saw a long procession, deformed in body and warped in mind, some with illness of the flesh, weak hearts or weak lungs, and some with illness of the spirit, languor of will, or a craving for liquor.
This murder in particular, there's no rhyme or reason to it,'' said Detective Mike Oppelt.
There's no rhyme or reason except maybe a budgetary need,'' said Oropeza.
IT DOESN'T make sense that only one poet in the last 15 years has won the Nobel Prize for Literature - there's no rhyme or reason for it.
Some days are better than others, there's no rhyme or reason for it.
Setting the rotation: Howland said he would like to establish an eight- or nine-man rotation, something unheard of the past few years since there appeared to be no rhyme or reason to some of former coach Steve Lavin's substitution patters.
It seems to be there was no rhyme or reason to this egregious crime.