The symbol ্ (হসন্ত, hasanta) is used to silence the inherent vowel a (the aw-sound as in “awful”, which for some reason is romanised as “a” instead of the more logical “o”).
That depends on the transliteration scheme, really, Wikipedia for example (
Bengali alphabet - Wikipedia) seems to have taken it upon itself to use
ô. But the reason presumably lies in the fact that Bengali is one of only a few (though there are others, such as Oriya) of India's languages in which the inherent vowel is pronounced with an
o-sound. It corresponds, though, with the inherent vowel in other Indian languages which is generally pronounced like the
u in
up and is usually denoted
a. I suppose it was considered helpful in internationalist, scholarly and linguistic circles to provide consistency in transliteration, but I should not be too surprised to find Bengali-specific material, from academic textbooks to text messages exchanged by native speakers in which a more Bengali-centric transliteration scheme is used. However, notice how the inherent vowel is denoted
a, even though it is pronounced much more like
u. So why isn't it
u then? Presumably because then you'd have nothing for the equivalents of Bengali উ/ঊ (i.e. Devanagari उ/ऊ, generally sounded (in the case of short
u) like the
u in
put and (in the case of long
ū) like the
oo in
too, or everywhere like the
oo in
too). Similarly in Bengali if we use
o for অ, what should we use for ও? And how should we reflect the fact that অ is traditionally counted as the short counterpart of long আ? Should আ then logically be
ō?
The point I raised above about consistency is underlined by the fact that the Bengali alphabet isn't only used for the Bengali language. It was in fact designed around Sanskrit and did you know that the first ever text to be printed in Sanskrit was printed in Bengali letters? So I would say there's a bit more to that point than just Britishers not caring!
However, this symbol is often neglected in Bengali writing, and many times, for consonant clusters, the consonants are written separately instead of using the conjuncts. Take as an example “লিফট”, which is pronounced as “lift” (if I were to phonetically transcribe it in Bengali, লিফ্ট্) but written as if it was “lifata” (a representing the aw-sound). Is there any way to predict if the inherent vowel is not pronounced without the need of hasanta?
And is there any way to know when the inherent vowel is pronounced অ and when it’s pronounced ও?
As lazy and self-defeating as it is to simply refer to an online article (and a Wikipedia article at that) I really feel you'd benefit from a broader understanding of "schwa deletion" in Indian languages. Indian languages vary in the extent to which Sanskritic
a is deleted, and Bengali is actually one of the more likely to retain it. Hindi and Punjabi delete Sanskrit
a in many places, for example at the ends of words (hence Sanskrit and English
Rama becomes Hindi
Ram (Gandhi's last words of course being
'He Ram!' (Oh God!)), which is the cause of ceaseless wondering among native speakers of languages like Hindi about why the English can't seem to pronounce
Ram properly even though they can manage to say
am and
arm in their own language. It also gets deleted in other positions, and even when words end in consonants. Thus you end up in Hindi with the word जन्म 'birth'. This is Sanskrit
janma, but in Hindi the
a is deleted at the end of the word, so you get
janm. But that's not that easy to say, so some people will put the vowel back in. But not at the end of the word, where it was in Sanskrit, but between the consonants, giving you a word that is spelt with a conjunct but pronounce
janam. Now let's see what happens when this word is compounded with दिन (Sanskrit
dina, Hindi
din) meaning 'day'. We get जन्मदिन, which in Sanskrit was
janmadina as it's written, but (much to my consternation!) in Hindi it is usually read
janamdin. So you have a conjunct between
n and
m, but a vowel is said between them, and then you have the inherent vowel written between
m and
di, but they're pronounced as a conjunct! And I would point out that this is a bit silly, but then I would have to defend
knight, or
thought and frankly I can't really do that! (The foregoing was of course intended to be humorous, but as that doesn't always come across on the internet, I just wanted to be clear that English spelling generally has its justifications and Indian spelling is generally much more logical than English at least!)
Schwa deletion in Indian languages - Wikipedia
It is generally the case that direct loans from Sanskrit (in much the same way that English treats loanwords in its spelling, which is the cause of some of the irregularities of English spelling) are spelt as they were in Sanskrit. Even if the normal rules of schwa deletion would make conjuncts unnecessary in modern Indian languages, conjuncts will be used in the spelling if they were used in Sanskrit. With other words it is much more likely that the rules of schwa deletion will be left to take care of things.
I suppose there is also the matter of simplicity. For example, if you're borrowing an English word into an Indian language, a word like
badminton, say, you will need a conjunct for
ḍma (I'm not very familiar with the Bengali alphabet, but in Hindi, that's not really ideal, and that's just an example that immediately came to mind), or you will need the
virāma/halant/hasanta. Which is fine and everything, but it's a bit of unnecessary pain in the backside really, which is presumably why even the English don't tend to bother writing
hôtel, rôle, or
dépôt anymore, although we will normally go for
déjà vu, mêlée and
papier-mâché.
According, then, to Wikipedia
The Bengali equivalent for Schwa is
Open-mid back rounded vowel or [ɔ]. Bengali deletes this vowel at the end when not ending in a consonant cluster but sometimes retains this vowel at the medial position. The consonant clusters at the end of a word usually follows a
Close-mid back rounded vowel or [o]. For example, the Sanskrit word पथ (/pɐt̪ʰɐ/, way) corresponds to the Bengali word পথ /pɔt̪ʰ/. But the Skt. word अन्त (/ɐnt̪ɐ/, end) retains the end vowel and becomes অন্ত /ɔnt̪o/ in Bengali, as it ends with a consonant cluster.
However,
tatsama borrowings from Sanskrit generally retain the 'ɔˈ except in word-final positions and except in very informal speech.
That vowel in medial position are not always retained. For instance, 'কলকাতা' is pronounced as /kolkat̪a/, and not /kolɔkat̪a/ (although different pronunciations based on dialect exist, none pronounce it this way).
This isn't really that well-written actually, but it seems to answer your questions, assuming its information is reliable. In brief consonant clusters will be written if they were written that way in Sanskrit and if the rules of schwa deletion in Bengali would not result in a conjunct where one is desired. If the word is etymologically descended from a word in which there was an inherent vowel but it has been lost by schwa deletion then a conjunct will not be written. See also what I said above about clarity and simplicity. At the end of the day, the Bengali script was not designed for some of the combinations of consonants you might get in foreign loanwords. From the perspective of Bengali this is simply a matter of learning the correct spelling, in much the same way that the student of English (whether native or foreign) does not need to know that
knight was once pronounced with a
k at the start and moreover that the
gh represents a sound much like the খ় [x] sound of Eastern Bengali which is also present in Assamese.
According to Wikipedia it seems that the inherent vowel is pronounced ও after a consonant cluster at the end of a word (see the অন্ত example).
Also from Wikipedia (
Bengali alphabet - Wikipedia):
The natural pronunciation of the grapheme অ, whether in its independent (visible) form or in its "inherent" (invisible) form in a consonant grapheme, is /ɔ/ [as in aw]. But its pronunciation changes to /o/ [ও] in the following contexts:
- অ is in the first syllable and there is a ই /i/ or উ /u/ in the next syllable, as in অতি ôti "much" /ot̪i/, বলছি bôlchhi "(I am) speaking" /ˈboltʃʰi/
- if the অ is the inherent vowel in a word-initial consonant cluster ending in rôphôla "rô ending" /r/, as in প্রথম prôthôm "first" /prot̪ʰom/
- if the next consonant cluster contains a jôphôla "jô ending", as in অন্য ônyô "other" /onːo/, জন্য jônyô "for" /dʒonːo/