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Trading Terminology

i here a few term in the trading world and unsure what they mean and cant seem to find the answer anywhere.
i here ocasionally that someone is a 'natural buyer of stock', and also 'non-natural'.
what do these terms mean?
Please can someone help
The public is normally a heavier buyer of stock since that is what they are told by tv and mutual funds 'be a buyer'. Thus they are natural buyers.