. (Aëronautics) The angle, esp. the least angle, at which a gliding machine or aëroplane will glide to earth by virtue of gravity without applied power. [ Webster 1913 Suppl. ]
adv. In a gliding manner. [ 1913 Webster ]
. (Aëronautics) A construction consisting essentially of one or more aëroplanes for gliding in an inclined path from a height to the ground. [ Webster 1913 Suppl. ]