/konz/ or /kons/ [LISP, "construct"] A Lisp function which takes an element H and a list T and returns a new list whose head is H and whose tail is T.
In Lisp, "cons" is the most fundamental operation for building structures. It actually takes any two objects and returns a "dotted-pair" or two-branched tree with one object hanging from each branch. Because the result of a cons is an object, it can be used to build binary trees of any shape and complexity.
[Jargon File]
Computing Dictionary