undertow

/ˈʌn.dɚ.toʊ/

名词

水下逆流；（尤指）退浪，回卷
Watch out for the powerful undertow at this beach - it can quickly pull swimmers out to sea if they're not careful.
在这个海滩要注意强劲的潜流，如果游泳者不小心的话它会很快将他们拖向海里。