back end

Meanings

1. The rear, back, or unseen portion (of something).
2. That part of a hardware or software system that is farthest from the user; the internals rather than the user interface.
3. The latter end of any given time, especially the latter part of the year; autumn; late autumn.
4. Money paid on a contingent deferred basis, for example, as a proportion of the profits or revenue of a work.
5. The processing of spent fuel from a nuclear reactor into reusable materials.