Dravida and Tamil are synonyms
Possible meaning of Tamil and Dravida in sanskrit:
The name of the TAmil (dAmil) people can mean the people of warm land:
दा f. dA (dam) heat
ilā (इला) refers to “earth”.
Thier Dravid name could also mean the people of the warm land:
द्राव m. drAva heat
iḍā (इडा) refers to “earth”.
Dravida and Tamil introductory etymology:
The origin of the Sanskrit word drāviḍa is Tamil. In Prakrit, words such as “Damela”, “Dameda”, “Dhamila” and “Damila”, which later evolved from “Tamila”, could have been used to denote an ethnic identity. In the Sanskrit tradition the word drāviḍa was also used to denote the geographical region of South India. Epigraphic evidence of an ethnic group termed as such is found in ancient India where a number of inscriptions have come to light datable from the 6th to the 5th century BCE mentioning Damela or Dameda persons. The Hathigumpha inscription of the Kalinga ruler Kharavela refers to a T(ra)mira samghata (Confederacy of Tamil rulers) dated to 150 BCE. It also mentions that the league of Tamil kingdoms had been in existence for 113 years by that time. In Amaravati in present-day Andhra Pradesh there is an inscription referring to a Dhamila-vaniya (Tamil trader) datable to the 3rd century CE. Another inscription of about the same time in Nagarjunakonda seems to refer to a Damila. A third inscription in Kanheri Caves refers to a Dhamila-gharini (Tamil house-holder). In the Buddhist Jataka story known as Akiti Jataka there is a mention to Damila-rattha (Tamil dynasty).
While the English word Dravidian was first employed by Robert Caldwell in his book of comparative Dravidian grammar based on the usage of the Sanskrit word drāviḍa in the work Tantravārttika by Kumārila Bhaṭṭa, the word drāviḍa in Sanskrit has been historically used to denote geographical regions of southern India as whole. Some theories concern the direction of derivation between tamiẓ and drāviḍa; such linguists as Zvelebil assert that the direction is from tamiẓ to drāviḍa.