Today's AWAD "mitty" explains that "mitty" is a personality type inspired by Thurber's "The Secret Life of Walter Mitty" but "mitty" didn't become a "syndrome" until it was recognized by a psychologist writing in a British medical journal.

Thurber's 1947 story 'The Secret Life of Walter Mitty' was taken up by psychologist and 'Walter Mitty Syndrome' was put forward in a British medical journal as a clinical condition, which manifested itself in compulsive fantasising. The title character is a meek, mild-mannered, henpecked husband who escapes his mundane everyday existence via heroic fantasies.

Thurber invented a psychological disorder known as "The Lilies-and-Bluebird Delusion". I wish Dr. Bill was around to explain that delusion to us.

"The Nature of the American Male: A Study of Pedestalism" and "The Lilies-and-Bluebird Delusion" appeared as the first and fifth chapters in Is Sex Necessary?

P.S. Word has come back about a medical condition Mitty invented called "coreopsis".

"When Mitty was fantasizing being a surgeon, the patient
starts to have an adverse reaction, and Mitty exclaims:
'Coreopsis is setting in!' Coreopsis sounds like a
medical term, but is a genus of common flowers."

In the operating room there were whispered introductions: "Dr. Remington, Dr. Mitty. Dr. Pritchard-Mitford, Dr. Mitty." "I've read your book on streptothricosis," said Pritchard-Mitford, shaking hands. "A brilliant performance, sir." "Thank you," said Walter Mitty. "Didn't know you were in the States, Mitty," grumbled Remington. "Coals to Newcastle, bringing Mitford and me up here for a tertiary." "You are very kind," said Mitty. A huge, complicated machine, connected to the operating table, with many tubes and wires, began at this moment to go pocketa-pocketa-pocketa. "The new anesthetizer is giving away!" shouted an intern. "There is no one in the East who knows how to fix it!" "Quiet, man!" said Mitty, in a low, cool voice. He sprang to the machine, which was now going pocketa-pocketa-queep-pocketa-queep . He began fingering delicately a row of glistening dials. "Give me a fountain pen!" he snapped. Someone handed him a fountain pen. He pulled a faulty piston out of the machine and inserted the pen in its place. "That will hold for ten minutes," he said. "Get on with the operation. A nurse hurried over and whispered to Renshaw, and Mitty saw the man turn pale. "Coreopsis has set in," said Renshaw nervously. "If you would take over, Mitty?" Mitty looked at him and at the craven figure of Benbow, who drank, and at the grave, uncertain faces of the two great specialists. "If you wish," he said. They slipped a white gown on him, he adjusted a mask and drew on thin gloves; nurses handed him shining . . .

"Back it up, Mac!! Look out for that Buick!" Walter Mitty jammed on the brakes. "Wrong lane, Mac," said the parking-lot attendant, looking at Mitty closely.