Definitions of worse:

• noun:   something inferior in quality or condition or effect

  Example: "For better or for worse"

• adjective:   (comparative of `bad') inferior to another in quality or condition or desirability

  Example: "This road is worse than the first one we took"

• adjective:   changed for the worse in health or fitness

  Example: "I feel worse today"

• adverb:   (comparative of `ill') in a less effective or successful or desirable manner

  Example: "He did worse on the second exam"