If you feel as though your most recent meal may soon make a re-appearance, would you say, “I feel nauseous”?

If so, it might be helpful to know the “rest of the story” about nauseous, nauseated, and nauseating.

Consider the use of nauseous or nauseated in each of these sentences:

  1. Kenyatta, who is two-months pregnant, will miss the lecture this morning because she is nauseous.
  2. The smell of oatmeal makes me nauseated.
  3. Because his manners are very poor, Bernard often tells nauseous jokes at the dinner table.

What the Grammar Police Believe about Nauseous

Many prescriptivists (people who set forth rules for usage, such as the writers of style guides) distinguish carefully between the words nauseated and nauseous, arguing that to be nauseous means “to evoke nausea in someone else.”

They would say, then, that in sentence 1, nauseous is incorrect. Nauseated, they argue, is the better choice because the pregnant woman herself feels ill; she does not make others feel nauseated.

That opinion has been supported in the past even by some descriptivists (people who describe how people actually use a word rather than prescribe how it should be used, such as the compilers of dictionaries).  The American Heritage Dictionary of the English Language traces the history of its waning insistence that nauseous means “causing nausea.”

What Language Historians Actually Know about Nauseous

Dictionaries (and descriptive linguists), however, tell us that there are many instances throughout history—and especially in common usage today—in which people have used nauseous to mean “experiencing nausea.”

One well-respected source, Merriam-Webster’s Collegiate Dictionary, gives two definitions for nauseous. The first definition is “causing nausea or disgust”;  in this sense, the word is synonymous with nauseating.

The second definition is “affected with nausea or disgust”; in this sense, the word is synonymous with nauseated.

Webster’s goes on to defend the second use of nauseous solely on the basis of overwhelming “current use.”

However, in a delightfully humorous usage discussion (seriously: who knew dictionary writers had such a sense of humor?), Webster’s goes on to explain that the use of nauseous to mean “to feel ill” goes back as far as the mid-nineteenth century.

Nauseous Isn’t Necessary

Although many people want to use nauseous to mean both “making others ill” and “being ill,” no one would use nauseated in both senses.

In the third sentence above, for example, we understand clearly that a joke cannot “feel queasy.” A joke, however, can be in such poor taste that it makes listeners feel ill; it can be, therefore, nauseous.

But most people would use the word nauseating in such cases, not nauseous.

The bottom line is that we have two words that leave no room for ambiguity: nauseated and nauseating. 

The usage note in Webster’s points out that the word nauseous actually “appears to be losing ground” to the words nauseated and nauseating, which have clearly different meanings.

So what do we advise? Perhaps the best idea is to get ahead of the curve and simply avoid the word nauseous altogether: use nauseated to mean “experiencing nausea” and nauseating to mean “causing nausea.”

If you choose, however, to use nauseous to mean “experiencing nausea,” be aware that although the dictionaries may be on your side, some people in your audience may misunderstand you or (wrongly) believe you have made an error in usage.

In most situations, such a response would be inconsequential. But in some high-stakes situations (the cover letter for a job application or a pitch to a new client, for example), it’s wise to keep in mind that people’s definitions of nauseous differ.

Other confusing word pairs are discussed elsewhere on this site. A few of the most popular are effect and affect , lay and lie , I and me ,  and which and that .

Copyright 2006 Get It Write. Revised 2019.