To extend an algebraic object (e.g. a field, a ring, etc.) by adding to it (an element not belonging to it) and all finite power series of (the element).
To be in contact or connection with.
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.