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Glite Dictionary
🇬🇧 A UK liquid unit 🇺🇸 A US liquid unit
fluid ounce

fluid ounce

2.8
A US unit for measuring small amounts of liquid equal to about 30 millilitres
  • noun
  • /ˈfluːɪd aʊns/
  • US
translation icon : onza líquida
  • When there are rivers to be forded, you will administer five fluid ounces of the laudanum.

Examples

  • He measured out exactly four fluid ounces for the experiment.

  • The recipe calls for eight fluid ounces of milk.

  • A standard soda can holds twelve fluid ounces.

Surface Forms

fluid ounce singular
fluid ounces plural

Morphology

fluid + ounce

The compound is compositional: 'fluid' (liquid) modifies 'ounce' (a unit/measure), so a learner who knows both words will infer it denotes a unit for measuring liquids. While the exact quantity (≈29.57 ml) is not predictable from the parts, the general meaning 'a volume measure for liquids' is directly derivable and this pattern is cross-linguistically common.

Etymology

Fluid ounce in the US comes from the idea of dividing a US pint into sixteen equal parts. If you imagine a pint bottle cut into 16 little cups, each cup is a fluid ounce, which is why Americans use it as a small unit for 'liquids'.