erosion
noun [ U ]
uk/ɪˈrəʊʒən/ usthe gradual reduction or destruction of something:
erosion of sth Investors may have seen some erosion of capital over the year.
erosion in sth The effect of this is that the erosion in the relative value of the pension will continue.
price/jobs erosion Intense competition and price erosion will force the company to cut 10% of its global workforce.