Merriam-Webster's Collegiate® Dictionary, 11th Edition
GOOSE
I. noun (plural geese)
Etymology: Middle English gos, from Old English gōs; akin to Old High German gans goose, Latin anser, Greek chēn Date: before 12th century
1. any of numerous large waterfowl (family Anatidae) that are intermediate between the swans and ducks and have long necks, feathered lores, and reticulate tarsi, a female goose as distinguished from a gander, simpleton , dolt , a tailor's smoothing iron with a gooseneck handle, a poke between the buttocks,
II. transitive verb (goosed; goosing)
Date: circa 1880
to poke between the buttocks with an upward thrust, to increase the activity, speed, power, intensity, or amount of ; spur