Accretion

akrecja

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

akrecja

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

akrecja

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

przyrost

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

przyrost

(something gradually added to or growing on a thing externally)