Dear Dinesh ji,
I think Holigarna grahamii can be called Vellai ceru, வெள்ளை செரு (in contrast to karunceru or black ceru, which is H. arnottiana), consistent with its Malayalam name Vellacheru.
The adjective vellai (= white) seems fitting as the plant features whitish flowers, white latex, pale greyish bark and glaucous leaves.
Best,
Vijayasankar