Collective Nouns
Collective nouns may take either singular or plural verbs, depending on whether the word refers to the group as a unit or to its members as individuals. In American English, most nouns naming a group regarded as a unit are treated as.
- Fifty percent of my time is spent on administration.
- Fifty percent of all physicians do not exercise regularly.
- The audience was enthralled.
- This gathering is becoming noisy.
- At noon today, the jury delivers its verdict.
For a unit of measure, use a singular verb.
- Five milliliters was injected.
- Two weeks of symptoms is common.
Latin and Greek vs. English
There is a trend toward using English plurals rather than the traditional Latin or Greek. However, in most cases the latest edition of Merriam-Webster’s Collegiate Dictionary or Dorland’s or Stedman’s medical dictionary should be followed. Consistency within a manuscript is key.
| SINGULAR | PREFERRED PLURAL |
| alga | algae |
| amoeba | amoebas |
| appendix | appendixes or appendices (consult dictionary for usage) |
| cannula | cannulas |
| condyloma acuminatum | condylomata, accuminata (with two-word Latin plurals, both parts become plural.) |
| cranium | crania |
| fistula | fistulas |
| formula | formulas |
| genus | genera |
| index | indices or indexes (consult dictionary for usage) |
| maxilla | maxillas |
| orbit | orbits |
| rhytid | rhytids |
| sequela | sequelae |
| vertebra | vertebrae |
Microorganisms
When referring to the common vernacular plural of a genus, use roman lowercase letters. Consult the latest edition of Dorland’s or Stedman’s medical dictionary. For organisms that do not have a common plural, add the word species or organisms to the genus name to indicate a plural use.
| GENUS | PLURAL NOUN FORM |
| Chlamydia | chlamydiae |
| Escherichia | Escherichia organisms |
| Mycobacterium | mycobacteria |
| Proteus | Proteus species |
| Pseudomonas | pseudomonads |
| Salmonella | salmonellae |
| Staphylococcus | staphylococci |
| Streptcoccus | streptococci |
When Not to Use Plurals
Beware of “pluralizing” nouns that cannot stand on their own as plurals.
Serum samples (not “sera”)
Urine tests (not “urines”)
False Singulars
Some nouns, because they end in a “plural” form, are mistakenly taken to be plurals even though they should be treated as singular and take a singular verb (e.g., measles, mumps, mathematics, genetics).
Measles is a deadly disease in underdeveloped countries.
A few nouns are usually used in the plural form; however, the distinction between plural and singular should be retained when appropriate.
| PLURAL | SINGULAR |
| data | datum |
| criteria | criterion |
| media | medium (for a specific type, television is a good medium for disseminating important health news.) |
| phenomena | phenomenon |
