x1 is a false, fake, apparent, pseudo-x2 (ka); x1 seems to be or do x2, but in fact doesn't.
Combining form -fol- (for use as an analogue of *pseudo-*, as in folske 'pseudoscience'). See also tcica 'deceive, dupe', fidna 'pretend'. This word does *not* mean the same as jitfa 'logically false'.