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noun ac·cre·tion \ə-ˈkrē-shən\

Simple Definition of accretion

  • : a gradual process in which layers of a material are formed as small amounts are added over time

  • : something that has grown or accumulated slowly : a product or result of gradual growth

Source: Merriam-Webster's Learner's Dictionary

Full Definition of accretion

  1. 1 :  the process of growth or enlargement by a gradual buildup: as a :  increase by external addition or accumulation (as by adhesion of external parts or particles) b :  the increase of land by the action of natural forces

  2. 2 :  a product of accretion; especially :  an extraneous addition <accretions of grime>

accretionaryplay \-shə-ˌner-ē, -ˌne-rē\ adjective
accretiveplay \ə-ˈkrē-tiv\ adjective

Examples of accretion in a sentence

  1. rocks formed by the slow accretion of limestone

  2. There was an accretion of ice on the car's windshield.

Origin of accretion

Latin accretion-, accretio, from accrescere — more at accrue

First Known Use: 1615

Medical Dictionary


noun ac·cre·tion \ə-ˈkrē-shən\

Medical Definition of accretion

  1. :  the process of growth or enlargement; especially :  increase by external addition or accumulation (as by adhesion of external parts or particles)—compare apposition 1, intussusception 2

accretionary \-shə-ˌner-ē\play adjective

Law Dictionary


noun ac·cre·tion \ə-ˈkrē-shən\

Legal Definition of accretion

  1. 1 :  the process or a result of growth or enlargement: as a :  the increase or extension of the boundaries of land or the consequent acquisition of land accruing to the owner by the gradual or imperceptible action of natural forces (as 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); also :  accession in which the boundaries of land are enlarged by this process — compare avulsion, reliction b :  increase in the amount or extent of any kind of property or in the value of any property <accretions to a trust fund resulting from the increase in value of…securities in which its corpus is invested — In re Estate of Gartenlaub, 244 P. 348 (1926)> Editor's note: Accretion in value of the principal of a trust is generally not considered income. c :  enlargement of a bargaining unit by the addition of new employees

  2. 2 in the civil law of Louisiana :  the passing to an heir or conjoint legatee of the right to accept a portion of a succession resulting from the failure of a coheir or colegatee to take his or her own share

Seen and Heard

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a timid, meek, or unassertive person

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