This hand movement is used when it comes to situations where you are explaining yourself to someone, placing emphasis on a point you want to get across and or even when you want to end the conversation. When a particular player or team is doing well, especially when it comes to football, they are our best friends and our gods.
Then you sort of move it away from and back towards your chest.
Or even when a Greek is supporting his/her favourite sports team, but they're losing? It's not always used aggressively, insultingly or angrily, but essentially endearingly.
And nope, it's not everyone's name, it actually means 'wanker'.
The action normally follows the words of some form of disbelief.