From Longman Dictionary of Contemporary Englishmake inroads into/on somethingmake inroads into/on somethinga) USE/CONSUMEto have an important effect or influence on something, especially by taking something away from it Video is making huge inroads into attendance figures at movie theaters (=taking away its customers). They have made significant inroads into the European market. The administrative workload is making massive inroads into our working day (=taking away time). b) to make some progress towards achieving something difficult We haven’t made much of an inroad into the backlog of work. → inroad