pre-order

from The Collaborative International Dictionary of English v.0.48

Preorder \Pre*or"der\, v. t.
   To order to arrange beforehand; to foreordain. --Sir W.
   Hamilton.
   [1913 Webster]

from The Free On-line Dictionary of Computing (8 July 2008)

pre-order

   1. <graph theory> {traversal}.

   2. <theory> A {relation} R is a pre-order if it is {reflexive}
   (x R x) and {transitive} (x R y R z => x R z).  If it is also
   {antisymmetric} (x R y R x => x = y) then it is a {partial
   ordering}.

   (2001-10-01)