from
The Collaborative International Dictionary of English v.0.48
Twain \Twain\ (tw[=a]n), a. & n. [OE. twein, tweien, tweyne, AS.
tw[=e]gen, masc. See {Two}.]
Two; -- nearly obsolete in common discourse, but used in
poetry and burlesque. "Children twain." --Chaucer.
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And whosoever shall compel thee to go a mile, go with
him twain. --Matt. v. 41.
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{In twain}, in halves; into two parts; asunder.
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When old winter split the rocks in twain. --Dryden.
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{Twain cloud}. (Meteor.) Same as {Cumulo-stratus}.
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