1 general:: see ON EARTH, def. 2.
American Heritage Idioms
2 general:: Phrase(s): like nothing on earth 1. Fig. very untidy or very unattractive. • Joan arrived at the office looking like nothing on earth. She had fallen in the mud. • Alice was like nothing on earth in that electric yellow dress. 2. Fig. very unusual; very distinctive. • The new car models look like nothing on earth this year. • This cake is so good! It’s like nothing on earth!
McGrawhill's American Idioms And Phrasal Verbs