a word of persian origin. means pussy in the farsi language.

someone who talks nonsense, someone who does something wrong, someone who ruins a flex, someone who adds something unessasary to a conversation, someone with no purpose etccc.

A company that makes good headphones.

a manufacturer of very nice sounding headphone

To be 'koss' is to be outragiously attractive and wanted by many.

May also be used to describe someone who has a good bum.

Of course, slightly extended and intertwind...

To koss - kossing - kossed
Listening to loud music through headphones without isolation in a public place, causing everyone around you to hear the music just as loud as you do.