unpromise noun 1verb 1forms 3 noun1 •Lack of promise; poor prospects; unpromising outlook.So I was a writer of early unpromise. All my stories from the age of twelve until I was at least twenty-two were pretty bad. — 2004 verb1 •To revoke or annul (something promised before).Promises are no fetters: with that tongue Thy promise past, unpromise it again. — 1605 formsunpromised · unpromising · unpromises