(1) Distribution channel through which originating mortgage lenders distribute mortgages to the Secondary Mortgage Market. Those purchasing mortgages distributed through the conduit re-sell them using the private market system. They are often converted into standardized mortgage investments as mortgage-backed investment securities. The mortgages are serviced either by the originating lender or by a service agency. (2) In construction, an enclosed channel or pipe used to carry electrical wiring, water, or other fluids. (3) A long restricted passageway between two walls.