Is ʀ and ʁ synonym in French (IPA)?

Question

I found that the ʀ and ʁ sounds are described differently depending on dictionaries.

For example, in this page, raison is written as the following:

ʁɛzɔ̃

But on my macOS dictionary, it is:

ʀɛzɔ̃

At first I thought it is synonym and depends on each dictionary. But I found that there is a difference, given that the wikipedia page ʁ and ʀ

rester [ʁɛste]

rendez-vous [ʀɑ̃devu]

So I'm confused. Are these two sounds same or different in French? If different, why is the macOS's and the linked page different and how can I know what IPA description is correct?

The wikipedia article writes the following:

Dialectal. More commonly an approximant or a fricative [ʁ]. See French phonology

Not sure what it means totally, but does that mean only some regions distinguish the two sounds?

Answer 1

Both are considered equivalent. The fact the r is fricative or trilled is mostly unnoticed but the trend is for speakers to use the [ʁ].

The letter r can also be realized with more ways by native and non native speakers. None of them prevent understanding.

See:
- https://www.verbotonale-phonetique.com/consonne-r-en-fle/
- https://fr.wikipedia.org/wiki/Phon%C3%A8me_/r/_en_fran%C3%A7ais
- https://en.wikipedia.org/wiki/Uvular_trill

Answer 2

In the IPA, the phonetic symbols ʀ and ʁ represent different physical sounds (phones). The IPA letter ʀ represents a voiced uvular trill and the IPA letter ʁ technically represents a voiced uvular fricative, but can also be used to represent an approximant, because IPA doesn't have a separate letter for a voiced uvular approximant.

If any regions distinguish the sounds, they must be very obscure: I've never heard of it, and the Wikipedia article isn't saying this. French only has a single "r" phoneme. The Wikipedia article is saying that ʁ occurs as a dialectal pronunciation of the "r" phoneme. In my experience, learners are usually advised to use a fricative or approximant pronunciation. There is a voiceless allophone [χ] that is described as being usual after voiceless consonants, and possible in other contexts. You can see some additional information on the phonetics of the French "r" phoneme in this article: http://linguistics.berkeley.edu/phonlab/documents/2014/Bakst_Katz_uvular.pdf