It originated in the language of the Maldives where "atolu" means a ring-shaped coral island.
Not too hard to find but you might not know that Bikini Atoll, the site of US nuclear tests in the late 1940s/early 1950s gave its name to the bikini swimsuit. (After the bombing there wasn't much of Bikini left.)
In those days the bikini was considered shocking simply because it showed a little bare midriff. By modern standards it was really a very modest two-piece that nobody would find offensive.
Paradoxically as the amount of cloth increased relative to the area of exposed skin, the prices went up when, obviously, the cost of manufacture went down. That's the rag trade for you. :(