\Un`der*mine"\, v. t.
1. To excavate the earth beneath, or the part of, especially
   for the purpose of causing to fall or be overthrown; to
   form a mine under; to sap; as, to undermine a wall.
         A vast rock undermined from one end to the other,
         and a highway running through it.     --Addison.
2. Fig.: To remove the foundation or support of by
   clandestine means; to ruin in an underhand way; as, to
   undermine reputation; to undermine the constitution of the
   state.
         He should be warned who are like to undermine him.
                                               --Locke.