If something proliferates, it grows and spreads quickly so that there is a great abundance of it.
Something or someone that is prolific is highly fruitful and so produces a lot of something.
The proletarian class in society is comprised of the workers or blue-collar class; they usually do not receive a salary but work for an hourly wage.
a member of the working class (not necessarily employed)
a social class comprising those who do manual labor or work for wages
growth by the rapid multiplication of parts
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