accretion
ah-KREE-shun
The gradual accumulation of material — in geology, the slow addition of sediment to a landmass by wave action, river deposit, or wind; in coastal geography, the building of a beach or shoreline by the delivery of sand faster than it is removed. Accretion is how land grows at the edges, grain by grain. The word also applies at planetary scale: the Earth itself was built by accretion, dust and rock gradually collecting into a sphere under the pull of gravity.
Etymology
Latin accretio, a growing, an increase, from accrescere, to grow toward. The land grows toward the water.
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