unsound

The best way to use this information, he thought, was to buy what appeared to be the sounder mortgage bonds and simultaneously sell the unsound ones.

The current directive is unconstitutional, discriminatory and scientifically unsound.

A charter school also can be denied renewal if it is fiscally unsound, but district staff concluded that, too, was not grounds for denial.

I joke to Shires that, as a man, most often the unsound advice I have received is to simply go look for a rebound.

The castle may have been demolished because it was structurally unsound or damaged in enemy attacks.