Calling All Linguists

[Politesse]

Anthropologist on board!

It's actually a longish answer, but I will try to pare it down.

What's happening here is that every language has a different set of customary sounds, what we call phonemes. There are actually more than a hundred potential sounds the mouth can produce, and the mind can distinguish between. IPA, the "linguist's alphabet", has a bunch of weird symbols for this very reason, so that there can be a symbol for each one in every language. Probably for simplicity's sake, no language uses all of them. Botswanan !Xoo, the most phonemically diverse language, tops out at 112. Most languages suffice with 50 or 60 in daily speech. This is one reason why languages "sound different", and why you can often guess what language someone is speaking without hearing any familiar words.

What happens to the other sounds, the unused phonemes? One of two things. One is that they just aren't used.
The other thing that happens is that similar sounds get bunched together, creating groups of related sounds that we call allophones. Speakers of a language may make, for instance, both "T" and "Th" sounds in the course of daily speech, but they use them interchangeably and indeed are unlikely to notice they've done it unless its pointed out. They were trained when they first acquired language to notice some sound differences (those that can change the meaning of a word in their language) and completely ignore others (those that are irrelevant to meaning). This can even happen between variants of the same language - for instance, UK English speakers often cap a vowel with an R-ish sound that they don't really think about but an American would find distracting.

Infants have no difficulty producing and imitating phonemes from any language, but by the age of 2-3, we lose our ability to notice phonemes that are allophones in our primary language, and will have to retrain from scratch if we want to, say, learn a new language with a different set. Which is not to say that you can't learn new phoneme distinctions, just that you won't do it instinctively until you've practiced for a while. What happened to you was probably a delay in parsing that one set of phonemes. It's a very likely allophone pair, since B and V are both voiced bilabials (sounds made by pressing the lips together and blowing) and allophones are most often sounds produced by the same part of the body.

 

[Fire_Monkey]

Hi!

When I was a child, and sometimes even now, I could not 'hear' the letter B; I always heard V. So, I would say, for instance, disturving, rugvy, kerv (for kerb), emvarrassed, etc.

As I became older I noticed this seems to be something of a linguistic phenomenon:

In Greek, a beta was pronounced like a B, now it is like a V (babarian is now varvare).
In Hebrew, Yakov, Avraham, Ovadia etc. for what we translate as Jacob, Abraham and Obadia etc.
In Spanish, also, the b and v have mixed.
In English we have changed what German has as a B to a V, as in gib (give), liebe (love), haben (have), silber (silver) etc.

Any explanations for why this occurs? Is there a name for it?

Your question is about a multitude of different phenomena which can't be explained with a single answer. But basically, those two letters are allophones.

That is....... and [v] as realized in English are both voiced as what we call "labial obstruents", which means they are extremely similar sounds.

They're in fact so similar that native speakers of languages in which they are not contrastive phonemes might not even recognize them as distinct sounds.

(This is the case for many Spanish speakers, for whom and [v] or [β] are in free variation or are allophones of the same /b/ phoneme.) So... ya get the frequent alternation of "b" and "v" in Spanish spelling (Spanish haber has a b where most other Romance language have a v)..

 

[Valjean]

Yes. In English a V (or F) is labio-dental, articulated by the upper teeth against the lower lip. In some other languages, though, the sound is articulated between the upper and lower lips -- no teeth involved. In that case the difference between Bs and Vs depends on how tightly you hold your lips -- which may vary between speakers.

Maybe this is why you'll see the capital of Cuba spelled with both a B and a V.

Is English your native language, Fire Monkey?