Grammar 101 with Michael Kwan

With a great number of posts in the Grammar 101 series, I discuss pairs of words that people may get confused for whatever reason. More often than not, the word pairs are homophones (words that sound the same) and at least one of the words is rarely found in casual writing. Today’s entry is a little different in that it’s more about having precision of language. Do you know what “supine” and “prone” mean?

Many people will tell you that it doesn’t matter if you have a minor grammatical error here or there as long as you get your point across. However, it is equally important to avoid any ambiguity in your writing. That way, you can avoid having your words twisted and misinterpreted. Be clear in your word choice, distinguishing between what it means to be “immoral” or “amoral”, or the difference between a newborn and a baby, for example.

In the case of the “supine” position and the “prone” position, both terms refer to lying down. The difference is that they are each more specific in describing how the person is lying down.

If you are in the supine position, then you are lying down on your back with your face up. In science and medicine, they may also use the term “semi-supine” to refer to someone who is still lying down with their face up, but the upper body could be tilted.

If you are in the prone position, by contrast, then you are lying down on your front with your face down.

The medical community once encouraged babies to sleep in the prone position, but today the supine position is more widely recommended.

As you can likely imagine, the related terms work in exactly the same way. Supination usually refers to the act of getting in the supine position, while pronation (not to be confused with the amateur nation… sorry) refers to the act of getting in the prone position.

There are some extensions to this concept outside of lying down. You might read about pronation of the foot, for example, which describes how the foot naturally rolls inwards when you walk or run. Supination can also refer to rotating your arm and hand so that your palm side faces upward (or forward if your arm is hanging by your side).

The easiest way to remember the difference between the two terms is that sUPination/sUPine refers to facing up, whereas prone/pronation refers to facing down. These words may not come up all that often, but now you have a clearer understanding of when to use which term.

Do you have a suggestion for a future Grammar 101 post? Post a comment below and I’ll add your idea to the queue.