An offensive word in the Arab world, which simplifies to "your mother's vagina". It also has different variations such as "Cos Omac Medaldel" which means "Your mother's Vagina dangles like the sleeve of a wizard". And it can be spelled in different ways such as "kos omak/cos omak/kos omac"
Cos - Vagina
Omac - Your mother
Dave I can't believe you ate my sandwitch, cos omac!

Michael cos omac I am trying to sleep.

Cos omac bro, your fart smells like shit.
by thewizewizard February 1, 2014
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