the.com/falseness

means The quality of being untrue, fake, or disloyal — when something or someone presents as genuine but isn't.

from Built from 'false,' which came through Old French 'fals' from Latin 'falsus,' the past participle of 'fallere' — to deceive or trip someone up. That same Latin root gives us 'fail' and 'fault,' so falseness and failure are etymological siblings: both descend from the idea of stumbling or being led astray. The '-ness' is just Old English's workhorse suffix for turning a quality into a noun.