Dravidian vs Tamil

Dravidian and Tamil both are nouns.

Word	Noun	Adjective	Verb	Adverb
Dravidian	Yes	No	No	No
Tamil	Yes	Yes	No	No

As nouns, Tamil is a hyponym of Dravidian; that is, Tamil is a word with a more specific, narrower meaning than Dravidian:

Dravidian: a member of one of the aboriginal inhabitants of India
Tamil: a member of the mixed Dravidian and Caucasian people of southern India and Sri Lanka

Other hyponyms of Dravidian include Badaga, Gadaba, Gond, Canarese, Kanarese, Kolam, Kota, Kotar, Kui, Malto, Savara, Telugu, Toda, Tulu.

Dravidian (noun)	Tamil (noun)
a large family of languages spoken in south and central India and Sri Lanka, as well as overseas in Malaysia and Singapore	the Dravidian language spoken since prehistoric times by the Tamil in southern India and Sri Lanka
a member of one of the aboriginal inhabitants of India	a member of the mixed Dravidian and Caucasian people of southern India and Sri Lanka

Dravidian (adjective)	Tamil (adjective)
	of or relating to a speaker of the Tamil language or the language itself