Astern and Abaft

Astern adverb - Near, toward, or in the stern of a ship or the tail of an aircraft.

Abaft is a synonym for astern in backward topic. In some cases you can use "Abaft" instead the word "Astern" as an adverb or an adjective or a preposition, when it comes to topics like aft.

Abaft adverb - Near, toward, or in the stern of a ship or the tail of an aircraft.

Astern is a synonym for abaft in behind topic. You can use "Astern" instead the word "Abaft" as an adverb or an adjective, if it concerns topics such as to the rear, aft.