The plural of חַבְרוּתָא

I have seen this often enough in speech and text that I felt this deserved a blog post. What is the plural of chavruta? Some say chavrutot, but this is in fact not correct.

The first thing to realize is that חַבְרוּתָא is not Hebrew. The first clue to this would be that it ends in kametz aleph, rather than kametz heh. The kametz aleph ending denotes the definite article in Aramaic. Let us look at some forms of the word חַבְרוּתָא.

Aramaic:
Absolute: חַבְרוּ = friendship
Construct: חַבְרוּת = friendship of
Definite: חַבְרוּתָא = the friendship
Definite plural: חַבְרְוָתָא = the friendships

The plural of the form is formed by changing the vowels, rather than by adding consonants to the word. We can use the definite plural rather than the absolute because in Babylonian Aramaic we often will have the definite ending on a word even when the word is not definite.

To compare, here is a word which has the definite plural form attested to:
Absolute: מַלְכוּ = kingship
Construct: מַלְכוּת = kingship of
Definite: מַלְכוּתָא = the kingship
Definite plural: מַלְכְוָתָא = the kingships

Compare with the Hebrew forms, choosing absolute plural rather than definite since it is more informative.
Absolute: חַבְרוּת = friendship
Construct: חַבְרוּת = friendship of
Definite: הַחַבְרוּת = the friendship
Absolute plural: חַבְרוּיוֹת = friendships

Absolute: מַלְכוּת = kingship
Construct: מַלְכוּת = kingship of
Definite: הַמַּלְכוּת = the kingship
Absolute plural: מַלְכוּיוֹת = the kingships

So even if we are going to choose the Hebrew form to make the plural of chavruta, it should be חַבְרוּיוֹת. After all, we do not say מַלְכוּתוֹת!

In fact, when people say chavruta, it seems to be the wrong word choice, for after all we are not talking about a friendship but a friend/learning partner. Perhaps this is based upon a misunderstanding of a gemara in the seventh perek of Bava Metzia, or in the third perek of Taanit. In Bava Metzia Rabbi Yochanan's mind turned after Resh Lakish died, and Rabbi Yochanan had no one to study with. The Rabbis prayed for him and he died. Thus, as people say, either friendship or death. The one in Taanis is about Choni Hameagel who slept through the Churban Bayit, had no equal, and people did not believe him: לא הימנוהו ולא עבדי ליה יקרא כדמבעי ליה חלש דעתיה בעי רחמי ומית אמר רבא היינו דאמרי אינשי או חברותא או מיתותא.

However, while this is taken to mean "either a friend or death," it likely means "either friendship or death." In constrast, in the 1st perek of Bava Batra, we have אמר רבא היינו דאמרי אינשי או חברא כחברי דאיוב או מיתותא

That is, "either a friend like the friends of Iyyov, or death." Thus, the word to describe a learning partner (/friend) in Aramaic should perhaps be חַבְרָא with the plural חַבְרִין.