Emily Dickinson Lexicon

TWAIN, a. [or n. Sax. twegen; Sw. tvenne; Dan. tvende, for tvegende. Whether two is contracted from tweg, is not apparent, but we see in the Danish tvende, the first syllable of twenty; twen-tig, two tens.]

Two. When old winter splits the rocks in twain. Dryden. [Nearly obsolete in common discourse, but used in poetry and burlesque.]