This is an all-in-one clue where the whole thing reads as a wry definition — economics being mocked as a dubious or "dismal" science. For the wordplay, take most of MOOT (dropping its last letter to give MOO) and most of SCIENCE (dropping its last letter to give SCIENC), and the word blurry tells you to jumble MOOSCIENC, which anagrams neatly into ECONOMICS.