ENGLISH
REFERENCE

proportional

adj. · n.
US //pɹəˈpɔɹʃənəɫ// UK //pɹəpˈɔːʃənəl// pro·por·tion·al
  1. 1 matching in size or amount (adj.)
    B2 Upper Intermediate Math

    changing in size, amount, or degree according to something else.

    corresponding in size or amount to something else; maintaining a constant ratio as another variable changes.

    Example

    The punishment should be proportional to the crime.

    Example

    The weight of the object is directly proportional to its mass, meaning that as mass increases, the weight increases at a constant rate.

    Usage

    Often followed by the preposition 'to'.
  2. 2 typography (adj.)
    C1 Advanced Technical Computing

    describing a style of printing where different letters take up different amounts of space.

    relating to a typeface where characters have varying widths based on their natural shape, rather than a fixed width.

    Example

    Most books use a proportional font because it is easier to read than a typewriter style.

    Example

    Proportional spacing allows the letter 'i' to occupy significantly less horizontal space than the letter 'm', resulting in a more aesthetically pleasing text block.
    • variable width
    • monospace
    • fixed width
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  1. 3 a proportion (n.)
    C2 Proficiency Archaic Math

    an old word for a portion or a ratio.

    a value or quantity that exists in a specific ratio to another.

    Example

    The old text discussed the mathematical proportional of the two circles.

    Example

    In his early seventeenth-century treatise, the author calculates the exact proportional required to balance the architectural load.

    Teacher's tip

    This noun sense is extremely rare in modern English; learners should use 'proportion' or 'ratio' instead.
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