A dull and boring person who lacks an imaginative spark. A person who is not scintillated by life and breaks no rules. He dresses plainly, speaks calmly and is dependable and faithful. He does not have any hobbies or any interests other than earning his bread and butter. He is common, found easily and pleased quickly.
"Oh! Tom is such a cardboard box. He completely lacks intuition, is a bore to communicate with as he has no fresh ideas of his own and peddles out mundane and dull facts all the time."