noun (n)

• an increase by natural growth or addition(noun.process)

  Synonym:
  accumulation
  

  source: wordnet30
• something contributing to growth or increase(noun.quantity)

  Example:
  He scraped away the accretions of paint.
  The central city surrounded by recent accretions.
  

  source: wordnet30
• (astronomy) the formation of a celestial object by the effect of gravity pulling together surrounding objects and gases(noun.process)

  source: wordnet30
• (biology) growth by addition as by the adhesion of parts or particles(noun.process)

  source: wordnet30
• (geology) an increase in land resulting from alluvial deposits or waterborne sediment(noun.process)

  source: wordnet30
• (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)(noun.possession)

  source: wordnet30
• The act of increasing by natural growth; esp. the increase of organic bodies by the internal accession of parts; organic growth.(noun)

  source: webster1913