Vagueness

n. unclarity; ambiguity

Ambiguity is one way in which the meanings of words and phrases can be unclear, but there is another way, which is different from ambiguity: vagueness. One example of a vague concept is the concept of a heap. Two or three grains of sand is not a heap, but a thousand is. How many grains of sand does it take to make a heap? There is no clear line. (See the paradox of the heap.)
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Noun
1. unclearness by virtue of being vague
(hypernym) unclearness
(hyponym) haziness

(n.)
The quality or state of being vague.
  

Uncertainty.

Certainty is required in contracts, wills, pleadings, judgments, and indeed in all the acts on which courts have to give a judgment, and if they be vague, so as not to be understood, they are in general invalid. A charge of "frequent intemperance" and "habitual indolence" are vague and too general.
   

This entry contains material from Bouvier's Legal Dictionary, a work published in the 1850's.