Astern
WordNet
adverb
(1) (of a ship or an airplane) behind
"We dropped her astern on the end of a seven-inch manilla, and she laid comfortably on the ebb tide"
(2) At or near or toward the stern of a ship or tail of an airplane
"Stow the luggage aft"
"Ships with square sails sail fairly efficiently with the wind abaft"
"The captain looked astern to see what the fuss was about"
(3) Stern foremost or backward
"The steamer went astern at half speed"