I often hear 全員 pronounced as ”ぜいいん”. I also read online that 雰囲気 can sometimes be heard as "ふいんき” although I have personally never heard that. I have a few questions about this phenomenon:
- Is there a name for this?
- Are there any more common examples of this that I should look out for in speech?
- Does it carry some nuance(e.g. street talk, old man, etc), possibly similar to what ないー＞ねえ carries?
- And finally, where am I most likely going to hear this(if at all)? Or in other words - is this a regional thing?