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synonymous

adj.
US //səˈnɑnəməs// UK //sɪnˈɒnɪməs// syn·ony·mous
  1. 1 having the same meaning (adj.)
    B2 Upper Intermediate

    having the same or a very similar meaning as another word.

    having the same or nearly the same meaning as another word or phrase in the same language.

    Example

    In many contexts, the word 'fast' is synonymous with 'quick'.

    Example

    Lexicographers often debate whether any two terms are truly synonymous or if subtle register differences always exist between them.

    Usage

    Usually follows the pattern 'X is synonymous with Y'.
    Pitfall
    The word 'big' is synonymous to 'large'.
    The word 'big' is synonymous with 'large'.

    Use the preposition 'with' after synonymous, not 'to'.

  2. 2 closely associated (adj.)
    B2 Upper Intermediate

    so closely connected with something that the two things seem the same.

    closely associated with or suggestive of a particular quality, idea, or brand.

    Example

    For many people, the brand name has become synonymous with luxury.

    Example

    The politician's name became synonymous with corruption following the scandal, making a return to public office nearly impossible.

    Usage

    Often used to describe reputations or brand identities.
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  1. 3 genetics (adj.)
    C2 Proficiency Technical Science

    describing a change in a gene that does not change the protein it makes.

    relating to a DNA substitution that does not result in a change to the amino acid sequence of the encoded protein.

    Example

    A synonymous mutation usually does not affect the health of the organism.

    Example

    The researchers focused on synonymous substitutions to estimate the background mutation rate without the interference of natural selection.
    • nonsynonymous
Origin

From Medieval Latin synōnymus, from Ancient Greek συνώνυμος (sunṓnumos). By surface analysis, synonym + -ous.

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