1 a current in the sea or ocean that moves in the opposite direction to the water near the surface 底流；水下逆流: The children were carried along by the strong undertow. 强大的回流把孩子们卷走。

2 undertow (of sth) a feeling or quality that influences people in a particular situation even though they are not really aware of it 潜在的倾向﹙或特质﹚；感染力