accretion Definition

accretion
noun

formal or technical:
1. An extra layer of material which has formed on something else.
2. The process of separate things growing into one.
3. geol.
A gradual increase in land area resulting from offshore deposition of sediment carried by river currents, tides or wave action.
4. An increase in size of a particle, eg a hailstone, as a result of the formation of additional outer layers.

Derivative: accretive
adj

Etymology: 17c: from Latin accretio growing together.