Definitions of hidden:

• adjective:   difficult to find

  Example: "Hidden valleys"

• adjective:   designed to elude detection

  Example: "A hidden room or place of concealment such as a priest hole"

• adjective:   covered from view

  Example: "Her face buried (or hidden) in her hands"

• adjective:   not accessible to view

  Example: "Concealed (or hidden) damage"

• name:  A surname (very rare: popularity rank in the U.S.: #47054)