Sentence:  Now , in 1961 , the Catholic population of England is still quite small ( ten per cent , or 5 <WSD>million</WSD> ) ; yet it represents a very considerable percentage of the churchgoing population . 
Meaning of the word marked with <WSD> tags:  (in Roman numerals, M written with a macron over it) denoting a quantity consisting of 1,000,000 items or units