Definition of "back end"

back end

noun
plural back ends
1. The rear, back, or unseen portion (of something).
2. (computing) That part of a hardware or software system that is farthest from the user; the internals rather than the user interface.
  Quotations
  Together, the MathDocument and PaperController classes comprise the MathPaper application's front end, while the Evaluator makes up the application's back end. This technique of having separate front and back ends is a common […]
  2002, Simson Garfinkel, Michael K. Mahoney, Building Cocoa Applications: A Step-by-step Guide, "O'Reilly Media, Inc.", page 295
3. (UK dialectal, Northern England, Scotland) The latter end of any given time, especially the latter part of the year; autumn; late autumn.
4. (entertainment, etc.) Money paid on a contingent deferred basis, for example, as a proportion of the profits or revenue of a work.
  Quotations
  so-called “back end” deals is speculative at best. Ideally, the author or book publisher will secure a percentage of gross revenues rather than net profits, but such deals are rare indeed.
  1995, Jonathan Kirsch, Kirsch's Handbook of Publishing Law, page 212
  How does the taking of “back end” compensation affect the creative control asserted by an actor?
  2003, Melvin Simensky, Entertainment Law, page 1222
  That kind of money, he can get a piece of anybody's back end he wants." “It's an industry phrase. Means if the picture is a big hit, he gets a share of the profits, sometimes even a percentage of gross.
  2004, Dean Koontz, The Face, page 64
  […] Miramax was going to buy out the U.S. and Canadian rights to the picture and terminate everyone else's participation for a payout that included a guaranteed amount for the back end, as well as bonuses if the film exceeded certain levels of U.S. box office performance.
  2013, Peter Biskind, Down and Dirty Pictures
5. The processing of spent fuel from a nuclear reactor into reusable materials.