Postalveolar sounds
From User talk:Rua
Hi, Do you know whether there is a difference between [sʲ] and [ɕ] (that is, a difference between the palatalized alveolar sibilants and the alveolo-palatal "fully palatalized" postalveolar sibilants)?
I don't really know. I suspect that there is, by some formal definition, but I have no idea if that difference matters in practice.
My understanding is that [ɕ] is effectively synonymous with [ʃʲ]; no language contrasts them, and it isn't even clear what the putative difference between them could be.