Mi Yodeya is a question and answer site for those who base their lives on Jewish law and tradition and anyone interested in learning more. It only takes a minute to sign up.
Sign up to join this community
When it comes to Shabbos, Rosh Hashanah, Succos and Pesach, their corresponding masechtos are all called after the shabbos/festivals (i.e. Masechta Shabbos, Rosh Hashanah, Succah & Pesachim). Yet when it comes to Yom Kippur the masechta is only called 'Yoma' which just means 'the day', there is nothing about atonement or the like in the name.
Are there any sources that speak why this is the case?
According to the gemara in Rosh Hashanah 21a, Yom Kippur was known in Babylon as "Yoma Rabbah" - The Great Day:
"רַב נַחְמָן יְתֵיב בְּתַעֲנִיתָא כּוּלֵּיהּ יוֹמֵי דְּכִיפּוּרֵי לְאוּרְתָּא אֲתָא הָהוּא גַּבְרָא אֲמַר לֵיהּ לִמְחַר יוֹמָא רַבָּה בְּמַעְרְבָא
It was related that Rav Naḥman had once fasted the entire day of Yom Kippur as usual. In the evening, toward the end of his fast, a certain man came and said to him: Tomorrow is the great day, Yom Kippur, in the West, Eretz Yisrael, and it is therefore necessary to fast tomorrow."
It seems that from here, the name was shortened to just "Yoma".
Edit: Professor Yaakov Epstein wrote a different explanation in his book "Introduction to the Mishnaic Text", vol. 2:
"סדר יומא-כיפורים. בבבלי ואצל הגאונים (רשימת שבה"פ שם ורש"ג באגרתו, 33, 47): סדר יומא; בירוש': כיפורים, וכן בכ"י ???1 והו' לו, הרמב"ם בהקדמתו ורשימת שבד"נ סןף קדשים, פי' הגאונים 57, 70, 128 והשואל באגרת רש"ג 33. השם המלא בעברית הוא: (סדר יום ה)כפורים, ובארמית: סדר יומא (דכיפוריא), בתוספתא כ"י ארפורט: יום הכיפורים, בכ"י ווינא: כיפורים."
The gist of what he says is that Yoma is a short-form of the Aramaic for Yom Kippur, but rather than the title "Yoma Rabbah", it's the literal translation: "Yoma Dekippurya".
1 Unclear letters in the copy I'm using.
The Maharsha (Rabbi Shmuel Eliezer Eidels) (quoted here, p. 2) answers in his work Chidushei Agadot that all you have to say is "the day" and it can be understood to mean Yom Kippur as this is the holiest day of the year.
R Dovid Bashevkin (in a Tablet article for the conclusion of the tractate) sees in the name of the tractate
... the first hint in unraveling the great mystery of Yom Kippur’s significance and enduring power. The ritual at the heart of Yom Kippur is time itself. Reading Tractate Yoma is a mystical journey. But the question is not where Tractate Yoma takes us, but when. [...] As Rav Yitzchak Hutner describes, “the Jewish experience of the Day of Atonement is an anticipation, a foretaste, a temporal and temporary incursion into history, of the end-time.” Yom Kippur is our time machine into the future.
So BS"D I just stumbled across the Bnei Yissascher, cheilek 2, maamar 8, os 2 (last paragraph) which asks this exact question!
He writes there:
והנה תמצא גם בתורה שבעל פה, המסכתא המדברת מענין מצות היום לא נקרא שמה על שם היום יום הכיפורים (כאינך שבת, פסחים, ראש השנה, סוכה) רק נקרא יומא, להורות קדושת היום הוא ממקום נעלם ראוי להסתירו, על כן מנהג אנשי מעשה שלא להזכיר שמו כל כך בפשיטות באיזה דברים, רק כשמזכירים מענינו לאיזה הצטרכות קוראים אותו סתם יום הקודש ודי בזה למשכיל (עיין ברכה משולשת פתיחה למסכת יומא)
And behold you find also with the Torah Sheba'al Peh (Oral Law), the tractate speak about the specific mitzvah of the day, yet it (masechta yoma) is not named after the day Yom Kippur (not like Shabbos, Pesachim, Rosh Hashanah, Succah) rather only it is called 'Yoma'? To teach you that the sanctity of the day is from a hidden place and is fitting to be concealed, therefore people of deeds don't mention its name as in the simple understanding, rather it is only when we are reminded of the subject matter and for what need it is called, that is just the Holy Day and that is enough to understand (Refer to the Bracha meshuleshes, in the introduction to masechta yoma).
