Definitions of commonplace:

• noun:   a trite or obvious remark
• adjective:   completely ordinary and unremarkable

  Example: "Air travel has now become commonplace"

• adjective:   not challenging; dull and lacking excitement
• adjective:   obvious and dull

  Example: "Commonplace prose"

• adjective:   repeated too often; overfamiliar through overuse

  Example: "His remarks were trite and commonplace"