Two;- nearly obsolete in common discourse, but used in poetry and burlesque. Children twain. And whosoever shall compel thee to go a mile, go with him twain. (Matt. V. 41) In twain, in halves; into two parts; asunder. When old winder split the rocks in twain. (Dryden) Twain cloud.
(Science: astronomy) same as Cumulo-stratus.
Origin: OE. Twein, tweien, tweyne, AS. Twegen, masc. See Two.