Definition of "undermine" []

• To weaken by wearing away a base or foundation: Water has undermined the stone foundations. (verb-transitive)
• To weaken, injure, or impair, often by degrees or imperceptibly; sap: Late hours can undermine one's health. (verb-transitive)
• To dig a mine or tunnel beneath. (verb-transitive)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "They have no respect for the Constitution because this power which they are trying to undermine, is specifically delegated to the President."
• "To expand on that, Washington seems to think that helping Israel keep up non-nuclear appearances might make Israel less inclined to once again undermine the Israel-Palestine peace process."
• "Has an ordinary man the courage to demand such sacrifices, and would not such efforts most certainly demoralise the Army, break up the bands of discipline, and, in short, undermine its military virtue, if firm reliance on the greatness and infallibility of the Commander did not compensate for all?"