Mainstream is defined as the popularly accepted trends, ideas, principles and values that are accepted by the majority of people.(noun)
The collective body of beliefs of the U.S. citizens are an example of the American mainstream.
The definition of mainstream is something considered customary or acceptable by a majority of people.(adjective)
Ideas that are in accordance with commonly held beliefs in a society are an example of ideas that would be described as mainstream.
See mainstream in Webster's New World College Dictionary
See mainstream in American Heritage Dictionary 4
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