I just checked out the Wikipedia entry:http://en.wikipedia.org/wiki/Runcible
which makes a fairly good case that runcible is a nonsense word coined by Edward Lear, who wrote The Owl and the Pussycat
. Lear also wrote of a "runcible hat", "runcible cat", "runcible goose" and a "runcible wall". But the wikipedia article goes on to list a variety of definitions that have sometimes been attached to "runcible spoon", which does include a spork-like utensil, so the definition that you discovered has some precedent in usage.