If you're nervous about swimming in the ocean, it may be because you were warned as a child about the undertow, or strong current, that might pull you beneath the surface.

When lifeguards or nervous parents talk about an undertow, they mean a rip current or rip tide, a channel that can form between breaking waves and has been known to pull swimmers rapidly out to sea. The term undertow isn't really accurate, since these currents won't pull you under the water. A figurative meaning of undertow is "underlying mood or feeling." For example, your festive birthday party might have an undertow of sadness if your best friend didn't show up.

Definitions of undertow
  1. noun
    the seaward undercurrent created after waves have broken on the shore
    synonyms: sea purse, sea puss, sea-poose, sea-purse, sea-puss
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    type of:
    undercurrent, undertide
    a current below the surface of a fluid
  2. noun
    an inclination contrary to the strongest or prevailing feeling
    “his account had a poignant undertow of regret”
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    type of:
    that toward which you are inclined to feel a liking
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