A socially acceptable level of income that provides adequate coverage for basic necessities such as food, shelter, child services, and healthcare.

Without some investment by our currency-issuing government in those things the disparity between what one can earn and what that will purchase will always be a problem. Every other modern democracy in the world has deemed healthcare as a responsibility of their government, be it direct management or simply "paying for" it. Many of those also supplement other expenses, such as housing, childcare, etc. for low-income earners, or everyone working for wages.

If we look at those expense items it isn't hard to see them equaling half of the expenses facing the average wage earner. By removing those expenses from the "free market" their profit potential is the only loss incurred as the employees in those industries are still required. It is our obsession with the free market and our misunderstanding of what constitutes "socialism" that is creating the wage quandary, not the wages themselves.