Sentence:  This long, dark cattle-shed is littered with jars of noxious chemicals, viscous brown liquids that reek of concentrated Prep School, and various rusted tins, scarily encrusted with <WSD>Marmitey</WSD> goop. 
Meaning of the word marked with <WSD> tags:  Resembling the food product Marmite in taste, texture, etc.