Twain

PIE word *dwóh₁ From Middle English tweyne, tweien, twaine, from Old English twēġen m (“two”), from Proto-West Germanic *twai-, from Proto-Germanic *twai, from Proto-Indo-European *dwóh₁. Cognate with Saterland Frisian twäin, Low German twene, German zween. More at two. The word outlasted the breakdown of gender in Middle English and survived as a secondary form of two, then especially in the cases where the numeral follows a noun. Its continuation into modern times was aided by its use in KJV, the Marriage Service, in poetry (where it is commonly used as a rhyme word), and in oral use where it is necessary to be clear that two and not to or too is meant.

PIE word *dwóh₁ From Middle English tweyne, tweien, twaine, from Old English twēġen m (“two”), from Proto-West Germanic *twai-, from Proto-Germanic *twai, from Proto-Indo-European *dwóh₁. Cognate with Saterland Frisian twäin, Low German twene, German zween. More at two. The word outlasted the breakdown of gender in Middle English and survived as a secondary form of two, then especially in the cases where the numeral follows a noun. Its continuation into modern times was aided by its use in KJV, the Marriage Service, in poetry (where it is commonly used as a rhyme word), and in oral use where it is necessary to be clear that two and not to or too is meant.

PIE word *dwóh₁ From Middle English tweyne, tweien, twaine, from Old English twēġen m (“two”), from Proto-West Germanic *twai-, from Proto-Germanic *twai, from Proto-Indo-European *dwóh₁. Cognate with Saterland Frisian twäin, Low German twene, German zween. More at two. The word outlasted the breakdown of gender in Middle English and survived as a secondary form of two, then especially in the cases where the numeral follows a noun. Its continuation into modern times was aided by its use in KJV, the Marriage Service, in poetry (where it is commonly used as a rhyme word), and in oral use where it is necessary to be clear that two and not to or too is meant.

From Middle English twaynen, from twayne (“two”, numeral) (see Etymology 1 above).

From twain, in reference to a line in Rudyard Kipling's poem The Ballad of East and West: "never the twain shall meet". This was chosen to reflect the difficulty, at the time, of connecting scanners and personal computers.

English surname meaning "divided in two," from the numeral/adjective twain.