Klein
/klaɪ̯n/noun
A German adjective meaning “small” or “little,” also used as a surname and in scientific terms such as “Klein bottle.”
Did you know?The mathematical “Klein bottle” was named after German mathematician Felix Klein, whose surname simply means “small” in German—not because the bottle is physically tiny.
Etymological Timeline
Proto-Indo-European (reconstructed)
PIE
*gelH-
“A disputed root associated with being compact, clumped, or tightly joined”
Proto-Germanic
PGmc
*klainiz
“Small, slender, or fine; the reconstructed ancestor of German klein”
Old High German
OHG
kleini
“Small, little, or fine”
Middle High German
MHG
kleine
“Small or little”
Modern German
German
klein
“Small, little, or minor”
19th Century
English
Klein
“An adopted surname and a technical name in mathematics, especially in “Klein bottle””