Definition
A structure or argument built on a shaky foundation.
How People Actually Use It
metaphor pertaining to something of a fragile or volatile nature. -from an old past-time of standing up playing cards together in the form of a house, this "structure" can fall apart at any time from the slightest action (e.g. an air current).
""We must plan this campaign implementing maximum precision, else it will disintegrate into a house of cards.""
Source: Urban Dictionary