mismate

Phyllie, don't mismate; those that do regret it.

From Tobogganing on Parnassus by Franklin P. (Franklin Pierce) Adams

Of the 1975 comedy-drama "Lucky Lady," for example, he wrote that it was a "cynical, vulgar, contrived, mismated, violent, uneven and uninteresting disaster."

From Los Angeles Times ● Nov. 17, 2014

One listener summed it up: "It didn't take Bernstein to show that they were mismated."

From Time Magazine Archive

Sometimes she gets kidded by Announcer Dick Willard and Husband Bill Sauter, a quiet, wisecracking ex-actor who contributes a felicitous conjugal note that draws plaintive queries from mismated listeners.

From Time Magazine Archive

Unaware or uninterested that the two are mismated, the matchmakers give their efforts much more sense of ravishment than of matrimony.

From Time Magazine Archive

The reflection came that the mismated in this present age must ordinarily bear the burden to the end.

From A Man and a Woman by Stanley Waterloo

The similar drug diethylstilbestrol, which Yale researchers are finding equally effective, has been used by veterinarians for years to treat mismating in animals.

From Time Magazine Archive

It was a most queer mismating, for the man was plain, sincere and honorable, and she was almost everything else.

From Little Journeys to the Homes of the Great Philosophers, Volume 8 by Elbert Hubbard

Social condemnation should stigmatize the wrong of mismating, not the undoing of such a wrong.

From Applied Eugenics by Paul Popenoe

However, they said very little about this mismating to any of their acquaintances, though sometimes Steve would look at James’s wife and sigh, and James would look at Steve’s wife and do the same. 

From Life's Little Ironies by Thomas Hardy

The contradiction and ludicrousness of this mismating is so easy of explanation that the incongruity is missed.

From Concerning Lafcadio Hearn With a Bibliography by Laura Stedman by George M. (George Milbrey) Gould