Dictionary entry overview: What does accretion mean? â¢ ACCRETION (noun) The noun ACCRETION has 6 senses: 1. an increase by natural growth or addition 2. something contributing to growth or increase 3. (astronomy) the formation of a celestial object by the effect of gravity pulling together surrounding objects and gases 4.
Great Barrier Reef. The Great Barrier Reef is the world's largest coral reef system composed of over 2,900 individual reefs and 900 islands stretching for over 2,300 kilometres (1,400 mi) over an area of approximately 344,400 square kilometres (133,000 sq mi). The reef is located in the Coral Sea, off the coast of Queensland, Australia.
The Great Barrier Reef off the coast of Queensland, Australia,  is the largest coral reef in the world, around 2300km long, with  its coral cays and islands spreading over 3 â¦ 00,000 square  kilometres. Considered one of the wonders of the natural world, the  Reef is unique for being visible from Earth's orbit.