iceberg

Iceberg is a partial calque of Dutch ijsberg, itself from Middle Dutch ijsberch, a compound of ijs ("ice") + berg ("mountain"). The "ice" half was translated into English while the whole shape of the compound was kept, and "ice" itself traces back through Old English īs and Proto-Germanic *īsą to Proto-Indo-European *h₁eyH-.

The word was first used to describe a glacier seen at a distance from a ship, then shifted to name the floating chunks of ice broken off from such glaciers. It later gained a figurative sense, pointing to the fact that only about one-tenth of an iceberg is usually visible above water.

It's cognate with German Eisberg, Danish isbjerg, Norwegian isberg, and Swedish isberg — all built from the same "ice-mountain" idea, each language having made its own version of the same compound.