twain \tweyn\,
adjective:
two.
Here two gentlefolks whisper together, and there other twain, their swords by their side.
-- Charles Reade, "The Cloister and the Hearth," 1861
Or one can say that East is East and West is West, and in American literature never the twain shall meet.
-- edited by Walter B. Rideout, "Sherwood Anderson: A Collection of Critical Essays," 1974
Twain comes from the Old English twēgen, which is the masculine nomiative and accusative form of the word "two."
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