the literal translation is: ur mum's punany!!!! but it means u want to have a wild ride with the mum in question.
its then one of the shortest way to start a nice discussion with an arab guy , discussion that will probably ended with a direct fist in the midle of ur face as the transcription of all the love involved between u and the persone ur talkin to . of course as all insults u can combine it in may ways
kos ommak ya ebn el sharmouta .
koss om abouk el a7beh el men7ata ....
and so on .
Kos-omak
An Arabic work that literaly translates (you mother's vagina)
However, it is used in the Arabic language to cuss someone else and is considered one of the strongest most offensive phrase you can say to a person. Always expect a fight after it.
An Arabic cuss word originally derived from Egyptian culture, literally meaning "your mother's pussy/vagina".
It's one of the mostoffensive things you can say to an Arab to the point that it can lead to fights sometimes depending on how it's used, so better watch your tongue.
It's usually used similarly to the cuss word "fuck you" in English, It may also be used as it's literal meaning depending on the context it was used in.
Example 1:
Omar: You're so bad at the game I won the match in just 10 seconds.
Ahmed: Kos omak!
(in this context it has similar meaning to "fuck you" in a less offensive manner.)
Example 2:
Wahab: To whom does this pencil belong to?
Adham: Belongs in kos omak.
(in this context it's used with the literal meaning of the word; "your mother's pussy/vagina" and thus sounding much more offensive than the other variant above. --Wahab must've picked a fight with Adham after he had disrespected him this way.)