the GNU version of the Collaborative International Dictionary of English
adj. Delusive; fallacious.
The Century Dictionary and Cyclopedia
Apt to deceive; deceptive; delusive.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
adj. causing one to believe what is not true or fail to believe what is true
Word Usage
"Elements of the administration are clinging to the "delusory" belief that Mr. Mubarak can hold on, said Robert Kagan, a foreign policy analyst at the Brookings Institution who has been a supporter of the president's foreign policy."