Move through water (4)
(Other definitions for wade that I've seen before include "Walk with legs partly immersed" , "Stride through river" , "Walk with effort through water" , "Walk through shallow water" , "Virginia who won Wimbledon" .)
'move through water' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for swim that I've seen before include "To be in the .... is knowing what is going on" , "Travel through water" , "Do the dog paddle, perhaps" , "Do crawl, perhaps" , "German submarine" .)