vague in WordNet English dictionary

1. 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"
   dim  faint  shadowy  vague  wispy 
   
2. 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
   obscure  vague 
   
3. not precisely limited, determined, or distinguished
   "an undefined term"; "undefined authority"; "some undefined sense of excitement"; "vague feelings of sadness"; "a vague uneasiness"
   undefined  vague