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The act of adding portions of soil to the soil already in possession of the owner by gradual deposition through the operation of natural causes.

The growth of the value of a particular item given to a person as a specific bequest under the provisions of a will between the time the will was written and the time of death of the testator—the person who wrote the will.

Accretion of land is of two types: (1) by alluvion, the washing up of sand or soil so as to form firm ground; and (2) by dereliction, as when the sea shrinks below the usual watermark. The terms alluvion and accretion are often used interchangeably, but alluvion refers to the deposit itself while accretion denotes the act. Land uncovered by a gradual subsidence of water is not an accretion; it is a reliction.


noun addition, advance, annexation, augmentation, enlargement, extension, gain, growth
See also: accession, accumulation, boom, collection, compilation, cumulation, development, enlargement, increase, increment


1 the natural increase in the area of land by accumulation of soil and the like. In Scotland the Roman term ALLUVIO is used for the same concept.
2 in Scotland, the term used in conveyancing to denote the fortification of a title by subsequent acquisition of ownership.

ACCRETION. The increase of land by the washing of the seas or rivers. Hale, De Jure Maris, 14. Vide Alluvion; Avulsion.