Ac*cre"tion (&?;), n. [L. accretio, fr. accrescere to increase. Cf. Crescent, Increase, Accrue.]
1. The act of increasing by natural growth; esp. the increase of organic bodies by the internal accession of parts; organic growth. Arbuthnot.
2. The act of increasing, or the matter added, by an accession of parts externally; an extraneous addition; as, an accretion of earth.
A mineral . . . augments not by grown, but by accretion.
Owen.
To strip off all the subordinate parts of his as a later accretion.
Sir G. C. Lewis.
3. Concretion; coherence of separate particles; as, the accretion of particles so as to form a solid mass.