The Plural of Prognosis: Here’s What It Is and How to Use It

The English language is a complicated collection of words and grammatical concepts borrowed from several other languages, which can make it arguably one of the most difficult languages to learn for people to understand it. It can be especially difficult for people who did not learn English at a young age. Many concepts do not seem to follow any general rules which can lead to several common grammar mistakes throughout English. 

One such word that is borrowed from other languages make to English is the word “prognosis,” pronounced prɒɡˈnəʊsɪs.  This word has a complicated background and history. In this article, let’s explore the proper use of our word of the day, prognosis, how to pluralize it, look for its synonyms, and learn its context.   

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What Does Prognosis Mean?

To understand a word and how to use it properly, you must first define it. According to the Merriam Webster Dictionary, the definition of prognosis is “the prospect of recovery as anticipated from the usual course of disease or peculiarities of the case.” This is not to be confused with the word “diagnosis,” which has a different meaning entirely. A diagnosis is the identification of a disease, whereas a prognosis is the course of a disease, which usually includes a prediction of the course the disease will take as well as the treatment. They are both medical terms, and therefore can be easily confused with one another. 

Prognostic scoring can be used for cancer outcome predictions from the doctor’s opinion in the medical community. There is something called a Manchester score, which is an indicator of prognosis in a specific type of lung cancer. For lymphoma, doctors have developed something called the “IPI,” also known as the “International Prognostic Index,” to aid in predicting prognoses. The index is a point system that uses factors such as age, and stage of cancer to make a more accurate prediction. 

Is Prognosis Singular or Plural?

Prognosis is a singular noun, used for describing one person’s prognosis. The correct plural of prognosis is “prognoses.” While this may seem odd at first, but there are actually several other words that follow this plural pattern. Words like “analysis” and “ellipsis” follow the same structure where the “is” is dropped, and an “es” is added to the end. The plural remains the same in both British English and American English.

Is Several a Plural?

When discussing the English language, one can sometimes be thrown off by a word. The word several seems like a singular word because it does not end is “s” or “es.” But this word is always used to describe more than one thing. It is most often defined as “more than one, but less than many.” It is used to describe something in the middle. One example would be “Specialists in several fields of medicine.”

What Is Another Word for Prognosis?

 It can be very beneficial to learn what the synonyms for a word are, which is where a thesaurus comes in handy.  Learning words with similar meanings is a great way to really cement a word into your vocabulary.  Here are some common synonyms for the word prognosis:

  • Foretelling: “To tell beforehand, to predict.”
  • Prophecy: “The prediction of something to come”
  • Auguring: “To foretell especially from omens.”

These synonyms are less medical in their usage but have a very similar general meaning. The prefix “pro” means “before,” so prognosis is closely related to knowledge beforehand of how something will turn out. 

The History and Origin of the Word

One of the best ways to understand a word is to learn where it came from.  A word’s etymology can reveal a lot about the changes a word has gone through to get to where it is today in modern English.  According to, the word origin for prognosis is from the 1650s and was used to mean “forecast of the probable course of disease.” It is from the Late Latin word prognosis and from the Greek prognōsis meaning “foreknowledge.” Prognosis was originally only used medically, but later the definition was broadened. It later took on the meaning of how a situation was likely to turn out. For example, economists can make a prognosis on what the economy is going to look like. 

Examples of the Word in Context

Another great way to learn how to use a word properly is to learn how to use it in context.  Reading or hearing someone else use the word correctly will cement it in your vocabulary.  Here are some example sentences of the word prognosis (and its plural form) being used in context:

  • “Right now, the doctors say the prognosis is good, and they expect him to make a full recovery.”
  • “The president of the company had a gloomy prognosis.”
  • “They decided to get married after his terminal cancer prognosis.” 
  • “She decided that she wouldn’t let her past prognoses define her life, regardless of the outcome of a disease.”

In Summary

A lot of singular nouns in English are made plural by adding an “s” at the end. But there are many rules regarding how to make a word plural depending on what letter the noun ends with. There are a lot of irregular nouns in English that do not follow any rules. Therefore, you must memorize them. After some practice with these words, the pluralization will come more naturally. 

Some of the words that change their ending must do so for the sake of pronunciation. If the word “bus” simply added an “s,” it would sound like the same word. If the word prognosis was pluralized by saying “prognosiss,” there would be no way to differentiate when you were saying the singular or the plural form of the word. This is part of the reason the English language has such peculiar rules—that, and the fact that English is made up of other languages.

Hopefully, after reading this article, you are equipped to use the word prognosis or prognoses in written or spoken communication. Good luck!