industrial reserve army; reserve army of labor
Marxist term for the pool of unemployed or underemployed workers that keeps wages down and is available for capitalist expansion.
In Marxian economics, the industrial reserve army is considered an inevitable product of capitalism.
the unemployed; jobless masses
More general, sometimes figurative use referring to the large number of unemployed people, often with a critical or social commentary tone.
The ranks of the unemployed are swelling due to the recession.