Tam: திருவல்லிக்கேணி tiruvallikkēṇi
‘Holy Lily Pond’ Locality (Chennai), Tamil Nadu
From Tam: t(h)iru, ‘sacred’, ‘auspicious’; alli, ‘water lily (the plant and the flower)’; and kēṇi, ‘pond’, ‘tank’.
Triplicane is a rather inventive British corruption of the original Thiruvallikeni.
Triplicane/Thiruvallikeni is much older than Chennai itself and may date back to the Pallava period
Triplicane was the first of the ancient seaside villages villages rented from the Sultan of Golconda in the late 17thC when Fort St George was expanded.
It is home to the 6-8thC Parthasarathy Temple dedicated to Krishna in his role as charioteer to Arjuna, as related in the Bhagavad Gita.
For related place names see Indian Place names and Tamil Nadu place names.

Sri Parthasarathy Temple, Triplicane (Chennai) Richard Mortel