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Nonpossessive Form 

Nonpossessive Form

Richard M. Glass

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Nonpossessive Form

There is some continuing debate over the use of the possessive form for eponyms, but a transition toward the nonpossessive form has taken place. A major step toward preference for the nonpossessive form occurred when the National Down Syndrome Society advocated the use of Down syndrome, rather than Down’s syndrome, arguing that the syndrome does not actually belong to anyone.6 The previous (ninth) edition of this manual,7 the seventh edition of the Council of Science Editors style manual,8 the Dictionary of Medical Eponyms,3 and the 27th edition of Stedman’s Medical Dictionary9 recommend and use the nonpossessive form for eponymous terms. However, the 30th edition of Dorland’s Illustrated Medical Dictionary takes an intermediate position, stating, “The use of the possessive form ending in 's for eponyms is becoming progressively less common, and the entries for eponymic terms in this Dictionary reflect this ongoing change in usage. The Dictionary therefore presents an inconsistent mixture of forms.”10

One reason for preferring the nonpossessive form is that, although eponyms are possessive nouns using proper names, they are structurally adjectival and should not convey a true possessive sense.1 For example, the name Addison, as used in describing “Addison’s disease,” is used as a noun modifier, with the sense of the modifier being clearly nonpossessive. Some possessive eponyms have evolved into the form of derived adjectives, as exemplified in the term addisonian crisis. Even when eponyms are used in an attributive sense, they have commonly lost possessive endings over time (eg, Nobel Prize, Petri dish). Thus, the transition of eponyms to the nonpossessive form is consistent with a linguistic perspective and also with trends in English usage.1

Use of the nonpossessive form of eponyms has become standard in medical genetics, and such usage, recommended by McKusick in Mendelian Inheritance in Man: A Catalog of Human Genes and Genetic Disorders,11 is appropriate in other areas of medicine. McKusick’s reasons for avoiding the possessive form of eponyms included the comment that “the eponym is merely a ‘handle'; often the person whose name is used was not the first to describe the condition… or did not describe the full syndrome as it has subsequently become known.”11 Hence, even the initial description may not belong to the named individual, providing an additional reason to avoid the possessive form.

The following examples illustrate the advantages of the nonpossessive form in particular categories of eponymous terms with regard to spelling and pronunciation.

  • When the word following begins with a sibilant c, s, or z (eg, syndrome, sign, zone)11:

    Bitot spots

    Looser zones

    Cullen sign

    Reye syndrome

    Korsakoff psychosis

    Schwann cell

  • When an eponym ends in ce, s, or z11:

    Betz cell

    Homans sign

    Colles fracture

    Meigs syndrome

    Fordyce disease

    Posadas mycosis

    Graves disease

    Wilms tumor

    Grawitz tumor

    Yates correction

  • When a hyphenated name is involved:

    Brown-Séquard syndrome

  • When 2 or more names are involved:

    Charcot-Marie-Tooth disease

    Dejerine-Sottas dystrophy

  • When an article (a, an, the) precedes the term:

    an Opie paradox

    a Schatzki ring

Occasionally, the nonpossessive eponymous term may appear awkward. This can often be addressed by using the before the term:

the Avogadro number

the Starling law

the Pascal principle

the Tukey test

Alternative stylings for eponymous terms may include the use of of:

angle of Virchow

circle of Willis

The possessive form is used when it is part of an established nonmedical eponymous name:

Russell’s viper

St John’s wort

The possessive form is retained if it is part of the name of an organization or was used in the original of a quotation or citation:

The Alzheimer’s Association

The possessive form is also retained for noneponymous terms describing disorders characteristic of certain occupations or activities:

coal workers' pneumoconiosis

woolsorter’s disease

gamekeeper’s thumb

In view of the adjectival and descriptive, rather than possessive, sense of eponyms, the advantages of the nonpossessive form in particular instances, the recommendations of authorities, and in keeping with the desire to promote clarity and consistency in scientific writing, we recommend (with the exceptions noted above) that the nonpossessive form be used for eponymous terms.

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