Sentence:  The <WSD>big</WSD> houses, and there are a good many of them, lie for the most part in what may be called by courtesy the valleys. You catch a glimpse of them sometimes at a little distance from the [railway] line,nb..., with their court of farm and church and clustered village, in dignified seclusion. 
Meaning of the word marked with <WSD> tags:  Of great size, large.