undertow
noun /ˈʌndətəʊ/
  /ˈʌndərtəʊ/
[usually singular]- a current in the sea or ocean that moves in the opposite direction to the water near the surface- The children were carried out to sea by the strong undertow.
 
- undertow (of something) a feeling or quality that influences people in a particular situation even though they may not really be aware of it