The phrase 'be deluded by' refers to being misled, deceived, or tricked into believing something false. Some synonyms for this phrase include being hoodwinked, beguiled, duped, or bamboozled. Another similar term is being fooled, misled, or bamboozled. One can also use the word deceived, conned, or swindled to describe the act of being deluded by someone or something. These synonyms are often used to describe situations where a person is made to believe something that is not true, often resulting in negative outcomes. It is therefore important to be cautious and not easily be deluded by false promises or misleading information.