The following is quoted from the Oxford Enlish Dictionary (Online version)...
8. a. The expression or application of creative skill and imagination, typically in a visual form such as painting, drawing, or sculpture, producing works to be appreciated primarily for their beauty or emotional power. Also: such works themselves considered collectively. Cf. a work of art at WORK n. 14.
Although this is the most usual modern sense of art when used without any qualification, it has not been found in English dictionaries until the 19th cent. Before then, it seems to have been used chiefly by painters and writers on painting.
The unmodified mass noun it is normally understood as referring to the visual arts; however, it may sometimes to extended to include music, literature, dance, drama, etc., though the plural form arts (see sense 7) is frequently used to indicate a broader range of creative activities.
Various styles of art are distinguished by descriptive nouns and adjectives identifying location, function, medium, object, etc.: body, cave, clip-, computer, folk-, high, op, performance art, etc.; modern, New, nouveau art, etc. (see the first element); see also ABSTRACT adj. 4d and REPRESENTATIONAL adj. 3.
It might be of interest to to receive alternative definitions (for Art) from other English language dictionaries (and not excluding other languages / perhaps you might translate?)