at, close to, or toward the stern or tail: Stow the luggage aft.
–adjective
2.
situated toward or at the stern or tail: The aft sail was luffing.
Origin: bef. 950; ME afte, OE æftan from behind, equiv. to æf- opposite + -t- suffix of uncertain value + -an suffix marking motion from; c. OFris efta, OS, OHG aftan, Goth aftana, ON aptan, Gk opís(s)ō behind; not akin to Gk apóoff
O.E. æftan "behind, farthest back," from superl. of O.E. æf, af, of "off," from P.Gmc. *af-, from PIE root *apo- "off, away" (cf. Goth. aftana "from behind;" see apo-). Now purely nautical.
[aft, ahft] 
Nautical, Aeronautics