Why do they write 'every right' instead of 'all rights' or 'any right'?

Question

Why do they write 'every right' instead of 'all rights' or 'any right'? Is it the choice of a style.

He had every right to sound annoyed.

From A Wind in the Door by Madelene L'Engle.

Answer 1

The idiomatic phrase "he had every right to X" means "he was fully entitled to X" or "no one would question his justification for X". X can be a thing that the person does as in

• He had every right to seek a second opinion.
• She had every right to leave without further discussion.

In these cases the phrase can be used wehre the subject actually did X, or where the subject did not do X, but the speaker is saying that s/he would have been justified in doing X.

X can also be a state, particularly an emotional state. For example:

• He had every right to be highly annoyed.
• She had every right to be quite excited.

Again, this can be used both when the subject does in fact experience the emotion, and then the subject does not experience it, but the speaker is indicating that the emotion would have been justified.

This can also be used when describing a facial expression:

• He had every right to look disgusted.
• She had every right to look devastated.

Again, this may describe the subject's actual expression, or a hypothetical expression when the speaker asserts would have been justified.

As the comment by FumbleFingers suggests, similar phrases using every/no/some/good/much/etc. right/reason/justification/cause/ can be used, with appropriately modified meaning. I think that "every right" and "no right" are the most commonly used variations.

Answer 2

This is an idiomatic usage meaning that there was no question that he should have sounded annoyed. Whatever happened to make him sound annoyed would have had the same effect on anybody.

Your other suggestions, 'all rights' and 'any right' are similar to 'every right' in their literal meanings, but they are not interchangeable in this phrase because it's a common idiom that is used to convey this meaning specifically. If I heard someone say, 'He had all rights to sound annoyed' I would just think that the speaker had gotten the phrase wrong.

In a similar way you can also say

He had every reason to do what he did.

meaning that nobody would question his decision to do it. Anybody would agree that it was the right thing to do.