Sentence:  Now again in the latter summer do those Kings of the Niblungs ride To chase the sons of the plunder that curse the ocean-side: So over the oaken rollers they run the cutters down Till fair in the first of the deep are the glittering bows up-thrown; But, shining wet and steel-clad, men leap from the <WSD>surfy</WSD> shore, And hang their shields on the gunwale, and cast abroad the oar; Then full to the outer ocean swing round the golden beaks, And Sigurd sits by the tiller and the host of the spoilers seeks. 
Meaning of the word marked with <WSD> tags:  of a shore, having lots of breaking waves