nonmainstream

As an adjective nonmainstream

is not mainstream.

As a noun null is

zero, nil; the cardinal number before einn.

As a noun terms

is .

As an adjective nonmainstream is

not mainstream.

Fringe is a synonym of nonmainstream.

As adjectives the difference between fringe and nonmainstream

is that fringe is outside the mainstream while nonmainstream is not mainstream.

As a noun fringe

is a decorative border.

As a verb fringe

is to decorate with fringe.

As adjectives the difference between mainstream and nonmainstream

is that mainstream is used or accepted broadly rather than by a tiny fraction of a population or market while nonmainstream is not mainstream.

As a noun mainstream

is that which is common; the norm.

As a verb mainstream

is to educate (a disabled student) together with non-disabled students.