The phrase "giant iceberg" refers to an extremely large piece of ice that has broken off from a glacier or ice shelf and is floating in the ocean. It is called "giant" because it is much bigger than a regular iceberg. Full definition
Ocean blooms in the wake of giant icebergs off Antarctica absorbed 10 to 40 million tonnes of carbon a year, the study estimated, roughly equivalent to annual man - made greenhouse gas emissions of countries such as Sweden or New Zealand. (reuters.com)
Like giant icebergs, the pumice fields remained a hazard to ships for years after the eruption. (scientificamerican.com)
Water freezing within the fractures would force the ice sheet apart, causing giant icebergs to break off. (discovermagazine.com)