Yo Mama in Arabic Poetry

In Qatr Al-Nada, Ibn Hisham quotes the following line of poetry:

والتغلبيون بئس الفحل فحلهمو فحلا وأمهمو زلاء منطيق

meaning,

The Taghlabis, how deplorable their sire is at being a sire
And their mother is a belt-wearing bow.

The author of the lines of poetry (not Ibn Hisham) is insulting Bani Taghlab (a Christian Arab tribe) in a low-blow: their men aren't really good at being men, and their mothers are very thin. He describes their women as, "bows" (as in, what an arrow is shot from) in reference to their extremely thin buttocks. Not only that, but they wear belts to make themselves look fatter.

So, there you have it, "Yo Mama so skinny..."