- the act or process of injuring, attacking, or destroying something or someone indirectly or by imperceptible degrees, often leading to a dramatic collapse: The undermining of Scottish Gaelic as a viable language resulted not from decrees, but from a gradual weakening of independent Scottish institutions.
- the act or process of weakening something or causing it to collapse by removing its underlying support, as by erosion: During the heavy rains, blocked sewers caused the flooding of the basement and the undermining of the wall by water.
- the act of digging or tunneling underneath something, as a military stronghold: The siege works were now close enough to allow the undermining of some of the bastions of the fortress.
- weakening something or someone gradually or indirectly: Seating students in rows, so they cannot see each other’s faces, has an undermining effect on their engagement.
- digging or tunneling underneath something, or removing or eroding its underlying support: The land along the shoreline collapsed because of undermining waves and currents.
