From Longman Dictionary of Contemporary Englishpaper tigerˌpaper ˈtiger noun [countable] an enemy or opponent who seems powerful but actually is not
Examples from the Corpus
paper tiger• Is it only a paper tiger, or does it really have teeth?• But it remains difficult to see how the paper tiger can avoid being shredded over the next two or three years.• That was only the first occasion that Chairman Khrushchev reminded Chairman Mao that the paper tiger had nuclear teeth. 