Bilateral Feet or Bilateral Foot: Which Is Better?

Bilateral foot/feet is actually a medical terminology, generally used to refer to a condition in which one lacks one or both arches, or when the arches are very low. This can cause the feet to lie flat on the floor affecting one’s posture. 

While you might hear a Doctor say, “Mr. Franklin has bilateral foot injury” a poet might prefer to say, “he has bilateral feet injury” yet, the puzzle remains, which is correct? Which is more acceptable; Bilateral feet, or bilateral foot? 

What Is the Difference Between Bi-lateral Foot and Bi-lateral Feet?

  • Bi-lateral feet refer to a specific medical condition, while Bi-lateral foot does not refer to that.
  • Bi-lateral feet usually refers to both legs while Bi-lateral foot doesn’t refer to both legs

Bi-lateral foot is a specific medical condition

Generally, bi-lateral feet and bi-lateral foot might mean the same thing in medical terms, however there might be need for specificity sometimes. A medical condition in which one or both feet are affected by a particular injury or abnormality, is referred to as “Bi-lateral foot”. 

For example, a fracture of both feet. On the other hand, bi-lateral feet are not a medical condition, rather it is only used to indicate the involvement of both feet in such disorder or injury. 

For example, if you say, “He has bilateral kidney disease” it means that both his kidneys are injured, in the same vein, you can say, “He has a bilateral feet disorder” meaning both his feet were affected.

Bi-lateral feet refers to both legs

Bilateral Feet or Bilateral Foot: Which Is Better?

According to the English language, it recognizes ‘feet’ as a plural noun while ‘foot’ is the singular form of “feet”. Therefore, it follows, grammatically speaking, that bi-lateral foot refers to a single leg/foot, while bi-lateral feet should be used when talking about more than one leg/both legs. 

Although, it is not uncommon to hear people use bi-lateral foot to refer to both legs, because it has generally been considered acceptable. 

Which Is Better, Bilateral feet or Bilateral foot?

With explanations above, it is easy to discern that, it is better to say “bilateral feet” than to say bilateral foot. This is because bi; means both or two, while lateral means on the sides, therefore, bilateral would literally mean; on both sides. 

Since the word bilateral indicates that what you’re talking about is up to two, and the subject has to match the verb, feet should be the appropriate noun to follow. 

The noun “foot” is an irregular noun, which means, it doesn’t become plural by simply adding S, rather the spelling changes from foot to feet. For example, the plural of the plural of “tooth” is “teeth”, since it’s also an irregular noun.

Bi-lateral already suggests that both legs are affected, since both means two, and anytime you talk about more than one of something, the plural form is used. 

For example, you cannot say “His two foots were amputated” or “His two foot were amputated” rather, it is, “His two feet were amputated” in the same way, it is correct to say bilateral feet and is grammatically wrong to say bilateral foot.

How to Use Bilateral Feet and Bilateral Foot in Sentences.

  • Bi-lateral feet can be used to emphasize the involvement of the two feet
  • Don’t add ‘S’
  • Bilateral feet and bilateral foot, can sometimes be used interchangeably

Bilateral feet emphasizes involvement of both feet

You can easily say, he has bilateral foot injury as a medical term, but that doesn’t really mean that it is on only one foot, as it is simply a medical terminology. 

But if you want to be specific that the bilateral foot injury affected both legs, then you Say, he has bilateral feet injury. 

However, when not communicating in medical terms, but among friends or a layman, if you say he has bilateral foot disorder, the person will assume that only one foot is affected. 

Therefore, to be more specific that both feet are involved, always say, bilateral feet and if you want to be specific for only one foot, you can say, bilateral foot.

Don’t add S

It is a grammatical taboo to add S to irregular nouns, as most irregular nouns have a different spelling altogether as its plural form. Don’t add S to foot, don’t add S to feet. 

You can’t say “The twenty men at the far end all have bilateral feets” just because it is more than two or “They have bilateral foots”

Bilateral feet and bilateral foot can sometimes be used interchangeably

Bilateral Feet or Bilateral Foot: Which Is Better?

In some specific situations, bilateral feet can be used interchangeably. This is a situation that is not specific to being one or more. For example, you can say, “They all have bilateral feet injury” and you can also say, “They all have bilateral foot injury”. 

Also if we have a situation where a group of people have bilateral injury with some affecting one leg and some affecting two legs, you can interchangeably use feet and foot. E.g. “Each one of them has bilateral foot/feet injury”


It is obvious that it is almost always safer to say, bilateral feet than to say bilateral feet, as it is the right grammar to use, wherever you are. Someone might argue with you, but when you bring out these facts, it becomes obvious that you’re right.

The puzzle has now been solved, Bilateral feet or bilateral foot, which is better? Without doubt, it is bilateral feet. 

Leave a Comment