The word "undermine" refers to the act of weakening or damaging someone or something gradually and often in a way that is not immediately obvious. It can be used in various contexts, such as relationships, plans, authority, or structures. For example, when someone spreads rumors about a colleague, they may be trying to undermine that person's credibility and position within the workplace.
The word "undermine" is derived from the Old English word "under" meaning 'beneath' and "mine," which comes from the Proto-Germanic "*minōnan," meaning 'to dig' or 'to excavate.' Therefore, it originally referred to the practice of digging from underneath to create instability.