IPA: /dɪˈluːʒəˌnɛri/
KK: /dɪˈluːʒəˌnɛri/
Relating to or characterized by false beliefs or perceptions that are not based in reality.
His delusionary thoughts made it difficult for him to see the truth.
Delusionary → It is formed from "delusion" (from Latin "delusio", meaning deception or misleading) and the suffix "-ary" (meaning pertaining to or connected with). The word "delusionary" refers to something that is related to or characterized by delusion or false beliefs.
Think of 'delusion' as a form of 'deception' and remember that 'delusionary' describes something connected to that deception.