Abaft \uh-BAFT\ or \uh-BAHFT\ , preposition;
1. To the rear of; aft of
1. In the direction of the stern; astern; aft
This nautical term dates to the 1400's from on baft, which evolved from Old English on bæftan ("backwards"), a combination of be + æftan ("by" + "aft"). Æftan is an Old English word that is actually a superlative of æf, which means "off," so æftan means "most back" or "from behind." The word dates to at least 937, though the nautical sense didn't arise until around the 1660's in Middle English.