English Language & Usage Stack Exchange is a question and answer site for linguists, etymologists, and serious English language enthusiasts. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Should not the "personality" have been pluralized in "Multiple Personality Disorder"?

Is the single usage of "personality" with prepending "multiple" a professional jargon or it is the correct English usage?

share|improve this question
up vote 6 down vote accepted

In compound adjectives of this kind, where the first element is a number (or, as in this case, a numeric adjective), the second element is indeed always in singular form. Examples include three-dog night (a night so cold that you have to curl up with three dogs for warmth), Six-Party Talks (about North Korea, a few years back), seven-layer cake, and so forth.

share|improve this answer

Also see "toothbrush," "orange grove," and "tool box." As Alex says above, compound constructions generally agree in number, such that if one item is singular (brush, grove, box), the other will agree with it even though referring to multiple items.

share|improve this answer
No. In compound constructions, the modifier usually does not take a plural ending, irrespective of the number of the headword ("toothbrushes", "orange groves"). (There are exceptions, particularly where the singular might lead to ambiguity, such as "solids modelling"). This is an example of a cross-linguistic phenomenon, where modifying words in a compound tend to lose grammatical morphology and take a stem or combining form. – Colin Fine Mar 7 '11 at 15:49
@TheRaven: Alex did not say that compound constructions agree in number (in fact he said the opposite). And they don't. – Mechanical snail Jul 9 '12 at 1:48

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.