vague

adj. hazy, faint, indistinct; ambiguous; uncertain

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.)
See more at Wikipedia.org...

Adjective
1. not clearly understood or expressed; "an obscure turn of phrase"; "an impulse to go off and fight certain obscure battles of his own spirit"-Anatole Broyard; "their descriptions of human behavior become vague, dull, and unclear"- P.A.Sorokin; "vague...forms of speech...have so long passed for mysteries of science"- John Locke
(synonym) obscure
(similar) unclear
2. not precisely limited, determined, or distinguished; "an undefined term"; "undefined authority"; "some undefined sense of excitement"; "vague feelings of sadness"; "a vague uneasiness"
(synonym) undefined
(similar) indefinable, undefinable
(see-also) indefinite
3. lacking clarity or distinctness; "a dim figure in the distance"; "only a faint recollection"; "shadowy figures in the gloom"; "saw a vague outline of a building through the fog"; "a few wispy memories of childhood"
(synonym) dim, faint, shadowy, wispy
(similar) indistinct

adj. hazy, vague, undefined; indefinite, indeterminate, indistinguishable; inscrutable, incomprehensible; indistinct, formless; obscure, shadowy

n. wave, surge, tide; vagueness, haziness, dimness; upsurge, outbreak

v. wander, roam

v. wander, roam; straggle