Strong's H8419תַּהְפֻּכָה: a perversity or fraud KJV:(very) froward(-ness, thing), perverse thing.
Meanings: Brown-Driver-Briggs (1906) and Strong's Hebrew Dictionary (1890), public domain, via the Open Scriptures Hebrew Bible Project (CC BY 4.0). TWOT numbers for reference only.
Root family 512: הָפַךְhāpak — turn, overturn; turn about, turn over, overthrow, change, transform, turn back, change into; turn oneself, be perverse, turn over to, be reversed, changed, overthrown, be upturned; turn this way & that, every way…