undermine
Pronunciation:
/ʌndəˈmaɪn/verb
Definitions
To dig underneath (something), to make a passage for destructive or military purposes; to sap.
To weaken or work against; to hinder, sabotage.
Example: The war efforts were undermined by the constant bickering between the allies.
To erode the base or foundation of something, e.g. by the action of water.