1. （气候等的）侵蚀，腐蚀
    Erosion is the gradual destruction and removal of rock or soil in a particular area by rivers, the sea, or the weather.

    e.g. As their roots are strong and penetrating, they prevent erosion.
           它们的根十分粗壮而且扎得很深，从而避免了受侵蚀。
    e.g. ...erosion of the river valleys.
           河谷的侵蚀

2. （权威、权利、信心等的）逐渐丧失，削弱
    The erosion of a person's authority, rights, or confidence is the gradual destruction or removal of them.

    e.g. ...the erosion of confidence in world financial markets.
           对世界金融市场心灰意冷
    e.g. ...an erosion of presidential power.
           总统权力的削弱

3. （支持的）减少;（价值的）降低;（货币的）贬值
    The erosion of support, values, or money is a gradual decrease in its level or standard.

erosion的解释

    e.g. ...the erosion of moral standards.
           道德沦丧
    e.g. ...a dramatic erosion of support for the program.
           对该项目的支持大幅减少