Sentence:  Footwear had always been a problem in the kayak. <WSD>Shoepaks</WSD> kept my feet warm and dry, but were stiff and heavy to wear in the little boat. Regular mukluks were light and flexible, but didn't work too well when they were wet. 
Meaning of the word marked with <WSD> tags:  A heavy leather, ankle-high shoe, similar to a moccasin in that it lacks a separate sole.