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REFERENCE

dietary

adj. · n.
US //ˈdaɪəˌtɛɹi// UK //dˈaɪətəɹi// di·etary
  1. 1 relating to food and health (adj.)
    B2 Upper Intermediate Medicine

    relating to the food you eat or to a special diet you follow for health or religious reasons.

    pertaining to the intake of food or to specific nutritional regulations and restrictions.

    Example

    The restaurant menu clearly marks any dishes that meet common dietary requirements.

    Example

    The doctor suggested several dietary changes to help manage his high blood pressure without relying solely on medication.

    Usage

    Usually placed before a noun, such as 'dietary habits', 'dietary needs', or 'dietary fiber'.

  2. 2 a fixed meal plan (n.)
    C2 Proficiency Formal Technical

    a fixed plan for what people in a place like a hospital or prison should eat.

    a prescribed system or schedule of food provided to the inhabitants of an institution.

    Example

    The hospital dietary was designed to provide patients with balanced nutrition during recovery.

    Example

    Historical records from the nineteenth-century prison show a strict dietary consisting largely of bread, gruel, and occasional servings of meat.

    Teacher's tip

    This noun sense is rare in modern conversation; learners will almost always encounter 'dietary' as an adjective.

Origin

From Medieval Latin diētārium (“book prescribing diet”), from Latin diaeta (“diet”).

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