The Greek adjective elephantinos means "made of ivory" or "of ivory." It derives from elephas (elephant, ivory). It appears once in the NT: Revelation 18:12, in the lament over fallen Babylon, listing the luxuries no longer traded — including "articles of ivory" (skeuē elephantina).
Ivory (elephantinos) in Revelation 18:12 represents the extreme luxury and excess of Babylon — the world system that organizes itself around wealth, comfort, and self-indulgence. The OT already condemned ivory as a mark of decadent wealth: Amos 3:15 warns that "ivory houses" will be destroyed; Amos 6:4 rebukes those who "lie on beds of ivory." In Revelation's lament, the merchants weep because no one buys their ivory anymore. The goods of Babylon are not evil in themselves, but when they become the supreme object of desire, they become idols — and all idols will ultimately be mourned.