In full "pseudologia fantastica" (also pseudologia phantastica) Brit./ˌs(j)uːdə(ʊ)ˈləʊdʒɪə fanˈtastᵻkə/ U.S./ˌsudəˈloʊdʒə faenˈtaestəkə/. A condition, often related to a more general mental illness or personality disorder, in which a person tells elaborate and fantastic stories, especially about himself or herself, as if believing them to be true, but readily changes or abandons them if challenged.