transitive verb Date: 14th century to excavate the earth beneath ; form a mine under ; sap , to wash away supporting material from under, to subvert or weaken insidiously or secretly , to weaken or ruin by degrees, see: weaken
UNDERMINE
Meaning of UNDERMINE in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012