philology vs arts

philology and arts both are nouns.

Word	Noun	Adjective	Verb	Adverb
philology	Yes	No	No	No
arts	Yes	No	No	No

As nouns, arts is a hypernym of philology; that is, arts is a word with a broader meaning than philology:

philology: the humanistic study of language and literature
arts: studies intended to provide general knowledge and intellectual skills (rather than occupational or professional skills)

Other hypernyms of philology include humanistic discipline, humanities, liberal arts.

philology (noun)	arts (noun)
the humanistic study of language and literature	studies intended to provide general knowledge and intellectual skills (rather than occupational or professional skills)