Accretion

accroissement

((gradual) increase by an external addition of matter; an instance of this)

accrétion

(increase by natural growth, especially the gradual increase of organic bodies by the internal addition of matter; amount of such growth)

accrétion

(process of separate particles aggregating or coalescing together; thing formed in this manner — see also concretion)

accrétion

(formation of celestial bodies by the aggregating of matter drawn together by gravity; growth of a celestial body through this process)