no, a household is a tax filer plus a spouse and any others claimed as dependents. if you are single with no children and file a tax return, you are an entire household yourself. the median income for adults employed fulltime is about 33% less than the median household figure, not half.
That's still not what the original poster was talking about. I didn't check his numbers, but involuntary partial employment is a thing, and I don't see a reason why those people shouldn't be counted.
