Sentence:  The voices of the <WSD>Millerites</WSD> were heard singing and shouting and exhorting each other to stand firm, and to see to it that their lamps were trimmed and burning, ready for the awful moment whenever it might come. Still - nothing happened! 
Meaning of the word marked with <WSD> tags:  One who followed the calculations of William Miller or his followers that the world would end on October 22, 1844; when it did not, the Great Disappointment occurred. The subsequent denominations his movement spawned include the Adventists, Jehovah's Witnesses and the (Campbellite) Restorationists.