What are "Shosei"?
Rashi: They are plunderers.
What is the meaning of "Safushu"?
Rashi: It is an expression of obesity.
Radak: It is an expression of increase, i.e. increasing flesh and obesity, like "u'Fishtem k'Eglei Marbek" (Mal'achi 3:20).
Why is it written Sismechi, Sa'alozi, Safushi and Sitzhali, and we pronounce them Sismechu, Sa'alozu, Safushu and Sitzhalu?
Radak: It is written feminine singular corresponding to the Kenesiyah (Klal), and pronounced plural, corresponding to the Rabim, the individual residents of Bavel.
What is the comparison to "Eglah Dashah"?
Rashi: The calf threshes grain and eats constantly (it is very fat). Radak - it is unlike a calf that plows, which does not eat [constantly]. This is according to the minority of texts, which have a Hei at the end of Dashah.
Radak: It constantly grazes in Deshe (grass), so it is fat. Dashah is written with an Aleph in place of Hei for feminine [conjugation]. It is To'ar (kind of animal). The Aleph of the root is omitted. Alternatively, the Hei is omitted; the Kamatz under the Aleph shows that the Hei was omitted (normally, it should be a Patach). The same applies to "ki'Shgagah she'Yotza 1 mi'Lifnei ha'Shalit" (Koheles 10:5). It should have said Dash'ah, like Mal'ah, or Dasha'ah, like Chachamah.
Radak citing Targum Yonasan: They will run like a fattened calf.
Radak implies that it should have said she'Yotz'ah, with a Hei. Indeed, we find this in Mishnayos, but in Tanach it always says Yotzeis! Perhaps he holds that it is past tense; it should have said she'Yatz'ah, with a Hei. (PF)
Why is Bavel compared to these matters?
Radak: You rejoiced when you destroyed My land, and you increased from the good of My land, like a fat calf, and you shouted and rejoiced like Giborim when you were victorious in war. You did not defeat My nation due to your strength, rather, due to My anger against them!
Malbim: This Nevu'ah applies to the time when Bavel will plunder My inheritance and rejoice - when Belshatzar made his party and rejoiced with the Kelim of the Mikdash that he plundered from Yisrael.
