Accretion
ACCRETION (from Lat. ad, to, and crescere, to grow), an addition to that which already exists; increase in any substance by the addition of particles from the outside. In law, the term is used for the increase of property caused by gradual natural additions, as on a river bank or seashore.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)