Possul

You should not use your best friends as witnesses as they may be considered prejudiced and may possibly be considered posul as witnesses.

Source: wiktionary

Perhaps you should avoid this Chabad house--by your standards their sefer torah is probably possul, since it's only been checked and fixed by a chalav stam drinker.

Source: wiktionary

I’ve seen many taleisim before, dose of Chayim and Yossel. But as for your tallis, I must say, dis iz definitely possul. I could vork on your tallis some more, but it really doesn’t pay. If I vere you, I vould buy a new tallis, and throw dis old von avay.

Source: wiktionary