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REFERENCE

residue

n.
US //ˈɹɛzəˌdu// UK //ɹˈɛsɪdjˌuː// residue
  1. 1 leftover substance (n.)
    C1 Advanced Technical Science

    a small amount of something that stays on a surface after the rest has been removed.

    the material or substance that remains after a process such as evaporation, combustion, or filtration.

    Example

    The sticker left a sticky residue on the window that was hard to clean.

    Example

    The laboratory analysis detected a chemical residue on the surface of the fruit, suggesting that pesticides had been applied shortly before harvest.

    Usage

    Often used as an uncountable noun when referring to a layer of material.
  2. 2 legal remainder (n.)
    C1 Advanced Formal Technical Law

    the part of a person's money or property that is left after all debts and specific gifts are paid.

    the portion of a testator's estate remaining after the payment of debts, funeral expenses, and specific legacies.

    Example

    After the house was sold and the bills were paid, the residue of the money went to charity.

    Example

    The will stipulated that the residue of the estate should be divided equally among the deceased's three grandchildren after all specific bequests were fulfilled.

    Usage

    Typically used in the context of wills and probate law.
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  1. 3 math remainder (n.)
    C2 Proficiency Technical Math

    the number that is left over after one number is divided by another.

    a representative element of an equivalence class; the remainder left after a division operation in modular arithmetic.

    Example

    In this calculation, we need to find the residue of seventeen modulo five.

    Example

    The student struggled to calculate the quadratic residue, a fundamental concept in advanced number theory and cryptography.
  2. 4 biochemistry unit (n.)
    C2 Proficiency Technical Science

    a single part of a larger molecule, like one link in a chain.

    a specific unit within a polymer, such as a single amino acid within a protein chain.

    Example

    The protein is made of a long string of amino acid residues.

    Example

    The researchers identified a specific cysteine residue that was essential for the enzyme's catalytic activity.
Origin

From Middle English residue, from Old French residu, from Latin residuum, neuter of residuus (“remaining”), from resideō (“I remain behind”). Doublet of residuum.

Word family

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