To mediate, to be an intermediate.
To arrange, in the manner of a broker.
Being between two extremes, or in the middle of a range.
Any substance formed as part of a series of chemical reactions that is not the end-product.
An intermediary.
Anything in an intermediate position.
To popularize, to normalize, to render mainstream.
To become mainstream.
To educate (a disabled student) together with non-disabled students.
Used or accepted broadly rather than by small portions of a population or market.
That which is common; the norm.
The principal current in a flow, such as a river or flow of air