A parody is a humorous or mocking imitation of something, using the same form as the original. To parody a poem, you have to write another poem.
A parody is a form of humor that spoofs — or satirizes — something using the same form. For example, shows like "Saturday Night Live" and "The Daily Show" parody newscasts by doing fake newscasts that look like the real thing. Comedians and comedy writers love to parody the President. Anything in the public eye could be the object of a parody.