To incorporate (something extra, often an amount of money) into something else (often a bill).
To put an expansion onto a building, usually a home.
To add, as an accessory to the principal thing; to annex
To write more data to the end of a pre-existing file, string, or other object.
To hang or attach to, as by a string, so that the thing is suspended
An instance of writing more data to the end of an existing file.