classical music. In technical musical usage this means music composed during the late eighteenth and early nineteenth centuries, characterized by the development of the sonata by such composers as Mozart. In popular use, however, the term is used to mean any serious art music as distinct from jazz, pop, or folk.
The definition of vague is something unclear, hazy or uncertain. An example of vague would be directions to a house that don't include street names. YourDictionary definition and usage example.
Here, then, are three sources of vague and incorrect definitions: indistinctness of the object, imperfection of the organ of conception, inadequateness of the vehicle of ideas. This is likewise the case with regard to perception: for the object of perception is, it appears, prior to the act of perception.