/im"euhl mahn', -meuhn/ , n.
a maneuver in which an airplane makes a half loop, then resumes its normal, level position by making a half roll: used to gain altitude while turning to fly in the opposite direction. Also called Immelmann turn .
[ 1915-20; after Max Immelmann (1890-1916), German aviator of World War I, who is said to have devised it ]