Obama sent troops to fight undefined mission in Afghanistan
And whereas the wants of the Californians were nebulous and undefined, the wants of the Okies were beside the roads, lying there to be seen and coveted: the good fields with water to be dug for, the good green fields, earth to crumble experimentally in the hand, grass to smell, oaten stalks to chew until the sharp sweetness was in the throat.
In computing (particularly, in programming), undefined value is a condition where an expression does not have a correct value, although it is syntactically correct.