Hastin
Hastin (हस्तिन्) is a term for elephant used in Vedic texts. Other terms for elephant include Ibha (इभ) and Vārana (वारण).
The elephant in the Rigveda
In Rig Veda 1.84.17 and 4.4.1. and probably other instances the Rig Veda seems to refer to elephants (e.g. Bryant 2001: 323), an animal that is native to South Asia. It has been speculated that some of these verses might be references to domesticated elephants. In RV 1.64.7, 8.33.8 and 10.40.4, "wild" elephants are mentioned.
Mrga Hastin
In the Rigveda and in the Atharvaveda, the term is translated as elephant (according to Keith and Macdonell, Roth and other scholars). In the Rig Veda, Mrga Hastin (animal with a hand) occurs in RV 1.64.7 and RV 4.16.14. An equivalent word for elephants in Tamil is "kaimmā" (கைம்மா) which also means "animal with a hand" (Kalithogai, 23; Purananuru, 368).
Ibha
RV 9.57.3 and RV 6.20.8 mention ibhas, a term meaning "servant, domestics, household" according to Roth, Ludwig, Zimmer and other Indologists. Other scholars like Pischel and Karl Friedrich Geldner translate the term as elephant. According to Sayana,Mahidhara and the Nirukta, ibha is translated as elephant. Megasthenes and Nearchos also connect ibha with elephant. The term ibha is only used in the Samhitas, and especially in the Rig Veda.