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ounce

n.
US //ˈaʊns// UK //ˈaʊns// ounce
  1. 1 unit of weight (n.)
    B2 Upper Intermediate American English British English

    a unit for measuring weight, equal to about 28 grams.

    a unit of mass in the avoirdupois system, equivalent to 1/16 of a pound or approximately 28.35 grams.

    Example

    The recipe calls for eight ounces of butter and two cups of flour.

    Example

    The postal clerk weighed the letter carefully, noting that it was just under one ounce and therefore required only a single stamp.

    Usage

    Often abbreviated as 'oz' in recipes and on packaging.

    • oz
  2. 2 unit of liquid volume (n.)
    B2 Upper Intermediate American English British English

    a unit for measuring liquids, equal to about 30 millilitres.

    a unit of liquid volume, though the US fluid ounce (approx. 29.6 ml) differs slightly from the British imperial fluid ounce (approx. 28.4 ml).

    Example

    The small bottle of perfume contains only one fluid ounce.

    Example

    Standard airline regulations typically limit passengers to carrying containers of three fluid ounces or less in their hand luggage.

    Usage

    Usually referred to as a 'fluid ounce' to distinguish it from the unit of weight.

    • fluid ounce
    • fl oz
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  1. 3 a tiny amount (n.)
    B2 Upper Intermediate

    a very small amount of something, usually a feeling or a quality.

    a figurative small quantity or scintilla of an abstract quality, such as common sense or evidence.

    Example

    If he had an ounce of common sense, he wouldn't go out in this storm.

    Example

    The defence attorney argued that there was not a single ounce of evidence to connect his client to the scene of the crime.

    Usage

    Commonly used in negative constructions or 'if' clauses to emphasize a total lack of a quality.

  2. 4 snow leopard (n.)
    C2 Proficiency Literary Science

    another name for a snow leopard, a large cat with pale fur and dark spots.

    a common name for the snow leopard (Panthera uncia), a large felid native to the mountain ranges of Central and South Asia.

    Example

    The ounce is a beautiful cat that lives high in the snowy mountains.

    Example

    In older natural history texts, the snow leopard is frequently referred to as the ounce, a term derived from the Old French 'once'.

    Teacher's tip

    This sense is rare in modern conversation; learners will almost always encounter 'snow leopard' instead.

Etymology 1

From Middle English ounce, unce, from Middle French once, from Latin uncia (“Roman ounce, various similar units”), ultimately from Proto-Indo-European *óynos (“one”). Doublet of a, one, inch, uncia, onça, onza, oka, ouguiya, and awqiyyah.

Etymology 2

From Middle French once, from Old French lonce (“lynx”), by false division (the l was thought to be the article), from Italian lonza, ultimately from Ancient Greek λύγξ (lúnx, “lynx”). Doublet of onza and lynx.

Idioms1 entry

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