Both of these words are translated as "sea." What's the semantic difference between them?
The usual Arabic word for “sea” is baḥrun, baḥrin, baḥran, al-baḥru etc. These are different inflections of the same word. The other word is yammun, yammin, yamman, al-yammu etc. (all with double mm). This word is quite rare. In the Qur’an it occurs only in the story of Moses and means both “sea” and “river” (specifically the Nile).
In the commentary of A-Safi (1) and the book Lisan Al-Arab (2) the word "الیمّ" is defined as “a very deep sea". Therefore, using this word when narrating the miracle of drowning Pharaoh's clan in a deep sea by the power of Al-Mighty Allah, is more eloquent.
The same word has been used in the story of Moses when he was born:
أَنِ اقْذِفيهِ فِي التَّابُوتِ فَاقْذِفيهِ فِي الْيَمِّ فَلْيُلْقِهِ الْيَمُّ بِالسَّاحِلِ يَأْخُذْهُ عَدُوٌّ لي وَ عَدُوٌّ لَهُ وَ أَلْقَيْتُ عَلَيْكَ مَحَبَّةً مِنِّي وَ لِتُصْنَعَ عَلى عَيْني
put him in the casket, and cast it into the river. Then the river will cast it on the bank, and he shall be picked up by an enemy of Mine and an enemy of his. I And I cast upon you a love from Me, and that you might be reared under My eyes.(20:39)
The word "الیمّ" put eloquently more stress on the great miracle of surviving a newly born baby from such a deep sea.
It is amazing that the word "الیمّ" has always been used in verses which narrate a miracle of Al-Mighty Allah except for one verse where Allah says:
قالَ فَاذْهَبْ فَإِنَّ لَكَ فِي الْحَياةِ أَنْ تَقُولَ لا مِساسَ وَ إِنَّ لَكَ مَوْعِداً لَنْ تُخْلَفَهُ وَ انْظُرْ إِلى إِلهِكَ الَّذي ظَلْتَ عَلَيْهِ عاكِفاً لَنُحَرِّقَنَّهُ ثُمَّ لَنَنْسِفَنَّهُ فِي الْيَمِّ نَسْفاً
He said," Begone! It shall be your [lot] throughout life to say," Do not touch me!" Indeed there is a tryst for you which you will not fail to keep! Now look at your god to whom you went on clinging. We will burn it down and then scatter it [s ashes] into the sea. (20:97)
This verse is about the story of Samiri when he produced for Bani Israel a calf [a lifeless] body and then they took it for God! The word "الیمّ" put an emphasis on humiliating their handmade God by burning it down, scattering its smashes into a deep see and annihilating it forever.
(1) Commentary of A-Safi Volume 2. Page 230
(2) Lisan Al-Arab Volume 12. Page 647
On the meaning of "Al-Bahr" البحر in Arabic
First of all it is necessary to understand that the Arabic term
Bahr بحر or al-Bahr البحر
Is not specifically a synonym of the English word "sea" as it is mostly used and understood or translated nowadays by Arabic speakers. It rather means and includes the opposite of "land" so it includes, seas, oceans, rivers and lakes as well as anything that meets the stated meaning in the understanding of early Arabs.
On the meaning of "Al-Yamm" اليم in Arabic
As for the term yamm يم or al-Yamm اليم both linguists and especially exegetes (authors of tafsirs) have a dispute on whether it is Arabic or not and if not which is the original language from which it was Arabized! Sheikh ibn 'Ashur sums up in his at-Tahrir wa at-Tanwir التحرير والتنوير saying while interpreting (7:136):
واليم : البحر والنهر العظيم ، قيل هو كلمة عربية . وهو صنيع الكشاف إذ جعله مشتقا من التيمم ؛ لأنه يقصد للمنتفعين به ، وقال بعض اللغويين : هو معرب عن السريانية وأصله فيها " يما " وقال شيدلة : هو من القبطية ، وقال ابن الجوزي : هو من العبرية ، ولعله موجود في هذه اللغات .
And al-Yamm: the sea and the great river. It was said that it is an Arabic word. This is what the author of Al-Kashshaaf created, as he made it a derivative of tayammum. Because it is intended for those who benefit from it, and some linguists said: It is expressed in Syriac and its origin is “yama.” Shaidla (His name -as far as I've researched- is Mahmood ibn abi al-Hassan ibn al-Hussain an-Naysaburi محمود بن أبي الحسن بن الحسين النيسابوري a scholar who died around 550 or 553 a.H. among his book is the linguistic tafsir Bahir al-Bayan fi Ma'any Mushkilaat al-Qur'an باهر البيان في معاني مشكلات القرآن) said: It is from Coptic, and Ibn al-Jawzi said: It is from Hebrew, and perhaps it is found in these languages.
ولعل أصله عربي وأخذته لغات أخرى سامية من العربية والمراد به هنا بحر القلزم ، المسمى في التوراة " بحر سوف " ، وهو البحر الأحمر .
Perhaps its origin is Arabic and other Semitic languages took it from Arabic, and what is meant here is the Sea of Qalzum, which is called in the Torah “the Sea of Suf,” which is the Red Sea.
Since al-Yamm was also a reference of the Nile river in othe verses we may read further in at-Tahrir wa at-Tanwir:
وقد أطلق اليم على نهر النيل في قوله - تعالى - أن اقذفيه في التابوت فاقذفيه في اليم وقوله فإذا خفت عليه فألقيه في اليم ، فالتعريف في قوله ( اليم ) هنا تعريف العهد الذهني عند علماء المعاني المعروف بتعريف الجنس عند النحاة إذ ليس في العبرة اهتمام ببحر مخصوص ولكن بفرد من هذا النوع .(Source)
Al-Yamm was used to refer to the Nile River in the words of the Almighty “[Saying], 'Cast him into the chest and cast it into the river” and His saying: “but when you fear for him, cast him into the river” The definition in his saying (Al-Yamm) here is the definition of the mental covenant according to the scholars of semantics, which is known as the definition of the genus among the grammarians since the emphasize is not concerned with a specific (kind of) sea, but to an individual of this type.
An attempt to point at the difference of usage in the qur'an
We can speculate why in the qur'an al-Yamm was used several times and al-Bahr was used instead elsewhere here are a few observations I'd like to share:
- The qur'an generally uses the term "al-Bahr" when citing Alalh's gifts, creation (see for example 16:14) and in cases of survival or deliverance of the believers.
- On the opposite, the qur'an uses the term "al-Yamm" to describe the fear and punishment
For example in the same situation Allah say once:
And [recall] when We parted the sea for you and saved you and drowned the people of Pharaoh while you were looking on. (2:50)
using the term "al-Bahr" while referring to the believers.
So We took him and his soldiers and threw them into the sea. So see how was the end of the wrongdoers. (28:40)
Speaking of their pursuers (Pharao and his army: the disbelievers) see also (51:40).
On the other hand seemingly:
- Al-Bahr is used to refer to something large and deep
- Al-Yamm is used to express that something is smaller
This needs an explanation one attempt to explain this is that Bani Israel have had already crossed a large amount of the Red Sea:
when Pharao and his soldiers were drowned
So Pharaoh pursued them with his soldiers, and there covered them from the sea that which covered them, (20:78)
so they were closer to the coast which means the place was less deep.
Another which mother would