Aft, in naval terminology, is an adjective or adverb meaning, towards the stern (rear) of the ship, when the frame of reference is within the ship, headed at the fore. Example: "Able Seaman Smith; lay aft!". Or; "What's happening aft?"The corresponding adjective, in distinguishing one feature of the vessel from another is after. See the caption to the right. Its antonym is forward. The corresponding preposition is abaft. For example, the mizzenmast is abaft the mainmast. Its antonym is before or, in a more clumsy form, forward of.