Take a dip (4)
I believe the answer is:
swim
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">take a dip</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for swim that I've seen before include "Go for a dip" , "To be in the .... is knowing what is going on" , "Float - feel dizzy" , "Crawl, say" , "Crawl, e.g." .)