ENGLISH
REFERENCE

supplement

n. · v.
US //ˈsəpɫəmənt// sup·ple·ment
  1. 1 dietary additive (n.)
    B2 Upper Intermediate Medicine

    a pill or powder you take to get more vitamins or minerals in your diet.

    a substance, such as a vitamin or mineral, taken orally to compensate for a nutritional deficiency or to enhance physical performance.

    Example

    He takes a daily vitamin supplement to make sure he gets enough iron.

    Example

    Athletes often use protein supplements to aid muscle recovery after intense training sessions, though experts recommend a balanced diet first.
  2. 2 extra document or section (n.)
    B2 Upper Intermediate

    an extra part of a book, newspaper, or report that gives more information.

    an additional section or document that provides further information, updates, or corrections to a primary publication.

    Example

    The Sunday newspaper comes with a travel supplement full of holiday ideas.

    Example

    The technical manual includes a supplement that details the software changes introduced in the latest security patch.
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  1. 3 extra cost (n.)
    C1 Advanced Formal

    an extra amount of money you pay for a special service or item.

    an additional charge or surcharge, often applied to travel or dining for premium services.

    Example

    There is a small supplement if you want a room with a sea view.

    Example

    The tour package price is based on double occupancy, so solo travellers must pay a single-room supplement.
  2. 4 geometry (n.)
    C2 Proficiency Technical Math

    the amount of an angle that must be added to another to make 180 degrees.

    the angle that, when added to a given angle, results in a total of 180 degrees.

    Example

    If one angle is 110 degrees, its supplement is 70 degrees.

    Example

    Students were asked to calculate the supplement of various obtuse angles to demonstrate their understanding of linear pairs.
  3. 5 to add to (v.)
    B2 Upper Intermediate

    to add something to another thing to make it better or more complete.

    to add an extra element to something so as to enhance or complete it. Transitive; typically takes a direct object.

    Example

    She works part-time in the evenings to supplement her student loan.

    Example

    The lecturer suggested that students supplement their core reading with academic journals to gain a deeper understanding of the topic.
Origin

From Latin supplementum (“that which is added to supply a shortage”), from supplere (“to provide something”).

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