[1] : The Collaborative International Dictionary of English v.0.48

accretion \accre"tion\ a^kkr=e"shu^n, n. l. accretio,
   fr. accrescere to increase. cf. crescent, increase,
   accrue.
   1913 webster
   1. the act of increasing by natural growth; esp. the increase
      of organic bodies by the internal accession of parts;
      organic growth. --arbuthnot.
      1913 webster

   2. the act of increasing, or the matter added, by an
      accession of parts externally; an extraneous addition; as,
      an accretion of earth.
      1913 webster

            a mineral . . . augments not by growth, but by
            accretion.                            --owen.
      1913 webster

            to strip off all the subordinate parts of his
            narrative as a later accretion.       --sir g. c.
                                                  lewis.
      1913 webster

   3. concretion; coherence of separate particles; as, the
      accretion of particles so as to form a solid mass.
      1913 webster

   4. a growing together of parts naturally separate, as of the
      fingers or toes. --dana.
      1913 webster

   5. law
      a the adhering of property to something else, by which
          the owner of one thing becomes possessed of a right to
          another; generally, gain of land by the washing up of
          sand or soil from the sea or a river, or by a gradual
          recession of the water from the usual watermark.
      b gain to an heir or legatee, by failure of a coheir to
          the same succession, or a co-legatee of the same
          thing, to take his share. --wharton. kent.
          1913 webster
see also:
crescent increase accrue 

[2] : WordNet (r) 2.0

accretion
     n 1: an increase by natural growth or addition syn: accumulation
     2: something contributing to growth or increase; "he scraped
        away the accretions of paint"; "the central city
        surrounded by recent accretions"
     3: astronomy the formation of a celestial object by the
        effect of gravity pulling together surrounding objects and
        gases
     4: biology growth by addition as by the adhesion of parts or
        particles
     5: geology an increase in land resulting from alluvial
        deposits or water-borne sediment
     6: law an increase in a beneficiary's share in an estate as
        when a co-beneficiary dies or fails to meet some condition
        or rejects the inheritance
see also:
accumulation 

[3] : Bouvier's Law Dictionary, Revised 6th Ed (1856)

accretion. the increase of land by the washing of the seas or rivers. hale,
de jure maris, 14. vide alluvion; avulsion.

Accretion >> A Words
Accretion, definition of term: Accretion
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