1. To gradually weaken or damage the confidence, loyalty, or endorsement that someone or something receives
The scandal began to undermine support for the president among voters.
O escândalo começou a minar o apoio ao presidente entre os eleitores.
2. To erode or reduce backing, assistance, or endorsement through subtle or indirect means
Spreading false information can undermine support for important public health initiatives.
Espalhar informações falsas pode enfraquecer o apoio a iniciativas importantes de saúde pública.