1. (n.) A mistaken belief; as, a delusion of grandeur\.

2. (n.) The act of deluding; deception; a misleading of the mind.

3. (n.) That which is falsely or delusively believed or propagated; false belief; error in belief.

aberrancy aberration acting affectation agnosia airy nothing apparition appearance artifice attitudinizing autism bamboozlement befooling block blocking bluff bluffing bubble calculated deception casuistry cheat cheating chicane chicanery chimera circumvention color coloring conning counterfeit daydream deceit deceiving deception deceptiveness defectiveness defrauding delirium deluded belief delusion of persecution delusiveness dereism deviancy disguise disorientation dissemblance dissembling dissimulation distortion dream dream vision dreamland dreamworld dupery eidolon enmeshment ensnarement entanglement entrapment equivocation errancy erroneousness error facade face fake fakery faking fallaciousness fallacy false air false belief false front false show falseness falsity fancy fantasy fault faultiness feigning feint figment flaw flawedness flight of ideas flimflam flimflammery fond illusion fooling four-flushing fraud front ghost gilt gloss hallucination hallucinosis hamartia heresy heterodoxy hoodwinking humbug humbuggery ignis fatuus illusion imposture kidding masquerade mental block mental confusion meretriciousness mirage misapplication misbelief misconception misconstruction misdoing misfeasance misinterpretation misjudgment mistake nihilism nihilistic delusion ostentation outward show outwitting overreaching paralogia peccancy perversion phantasm phantom pipe dream playacting pose posing posture pretense pretension pretext psychological block putting on representation ruse seeming self-contradiction self-deceit self-deception self-delusion semblance shade sham show simulacrum simulation sin sinfulness snow job song and dance sophism sophistry speciousness spoofery spoofing spuriousness stratagem subterfuge swindling trick trickery trickiness tricking trip unorthodoxy untrueness untruth untruthfulness vapor varnish victimization vision willful misconception window dressing wishful thinking wrong wrong impression wrongness