Since a ball (for playing football) is hollow, can I say about its hollowness or cavity?:
(1) A ball has hollowness. — (as far as I understand, "hollowness" is uncountable, i.e. without "a")
(2) A ball has a cavity. — (as far as I understand, "cavity" is countable, i.e. with "a")

Is (1) correct? If not, then why not?
Is (2) correct? If not, then why not?
What's the difference between (1) and (2)?

1 Answer 1


You COULD say it this way, but it would be considered very odd wording.

A fluent speaker would be much more likely to say, "The ball is hollow" than "the ball has hollowness". And even more likely to say, "The ball is filled with air."

"Cavity" is usually used to describe a defect, a hole that isn't supposed to be there. Or at least that is unexpected. Like if something punched a large hole in the side of your house, you might say, "There's a giant cavity in the wall of my house." Or, if you found an empty space beneath a building that was created by some natural phenomenon, or by an unknown human agent, you might say, "There was a large cavity beneath the building." But if someone built a parking garage under the building, you wouldn't normally call that a "cavity". So I wouldn't use "cavity" to describe the empty space inside a ball.

  • Could you not say "Joe dug a large cavity beneath his house to make a wine cellar"? Commented Mar 23, 2023 at 2:42
  • Most dictionaries say that a cavity is a hole in a solid object. A ball is designed as a 'skin' surrounding some air, so the space inside isn't really thought of as a 'cavity'. Commented Mar 23, 2023 at 9:22
  • @PeterJennings You could say that, and I suppose you would be understood. But I don't think that's something a fluent speaker would be likely to say. It has to do with connotations of a word. Like, a politician would be unlikely to say, "We are putting together a propaganda campaign to gain support for our policies." That might make sense by a dictionary definition of "propaganda", but people tend to think of propaganda as lies, so you wouldn't use it to describe your own words.
    – Jay
    Commented Mar 23, 2023 at 21:18
  • @KateBunting Yes. Actually I have the same problem with "hollow", you don't normally think of a flexible container as "hollow". But you might use the word for lack of a better one in context.
    – Jay
    Commented Mar 23, 2023 at 21:19

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .