lexicology vs linguistics

lexicology and linguistics both are nouns.

Word	Noun	Adjective	Verb	Adverb
lexicology	Yes	No	No	No
linguistics	Yes	No	No	No

As nouns, linguistics is a hypernym of lexicology; that is, linguistics is a word with a broader meaning than lexicology:

lexicology: the branch of linguistics that studies the lexical component of language
linguistics: the humanistic study of language and literature

Other hypernyms of lexicology include philology.

lexicology (noun)	linguistics (noun)
the branch of linguistics that studies the lexical component of language	the scientific study of language
	the humanistic study of language and literature