undermine

verb

1 the integrity of government statistics is being undermined:

subvert, sabotage, threaten, weaken, compromise, diminish, reduce, impair, mar, spoil, ruin, impede, hinder, damage, hurt, injure, cripple, disable, enfeeble, sap, shake;

whittle away, eat away;

informal foul up, botch, put the kibosh on, drag through the mud;

British, informal throw a spanner in the works of, queer the pitch of;

North American, informal throw a monkey wrench in the works of.

▷antonyms enhance, improve, strengthen.

2 we had no other way to break in but by undermining the building:

tunnel under, dig under, burrow under, excavate, sap.

3 the damp had so undermined the structure that the wall fell down:

erode, wear away, eat away at, chip away, undercut.

▷antonyms shore up, support.

undermine Oxford Dictionary of English