ABAFT

adv. in the direction of the stern, astern (Nautical)

prep. to the back of; aft of

Abaft is a nautical expression indicating a point that is behind a given part of a boat or ship. For example, "abaft the funnel" means behind the ship's funnel. (If not qualified, abaft means "behind the mid-point of a ship or group of ships".) Note that unqualified or in the "abaft the beam" form, abaft does not necessarily refer to a point actually on the ship; it may refer to a point some significant distance away.
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Adverb
1. 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"
(synonym) aft, astern

(prep.)
Behind; toward the stern from; as, abaft the wheelhouse.
  

(adv.)
Toward the stern; aft; as, to go abaft.
  

A point beyond the midpoint of a ship's length. (MARAD2)