accretion
n. C / Un. the slow process of adding small amounts of material to something over a long time. In geology, it describes how rocks or land grow by adding layers of sediment.
n. the gradual increase in size or complexity by the addition of external matter. In geological contexts, it refers to the process by which sediment or other material is deposited and consolidated onto a landmass or rock formation.
The river's accretion built up the sandbar over many years.
Geologists study the accretion of sediment along the coastline to understand how the landscape has changed over millennia.
The theory of continental drift suggests that the Earth's landmasses have grown through the accretion of smaller tectonic plates over hundreds of millions of years.
PIE word *h₂éd Learned borrowing from Latin accrētiō (“increase, increment”) + English -ion (suffix forming nouns denoting actions or processes, or their results). Accrētiō is derived from accrēscō (“to grow, increase”) + -tiō (suffix forming nouns denoting actions or processes, or their results); and accrēscō is from ac- (a variant of ad-, prefix meaning ‘to’, or having an intensifying effect) + crēscō (“to grow; to increase”) (ultimately from Proto-Indo-European *ḱer- (“to cause to grow; to grow; to nourish”)). Doublet of accrue, crescent, and increase.