Supple term used to describe activities or chat that is playful, intelligent and original. Banter is something you either posses or lack, there is no middle ground. It is also something inherently English, stemming as it does from traditional hi-jinks and tomfoolery of British yesteryear.

the descriptin of "having a good time"
can also be used in a variety of forms

banterphenalia
banter inducer
banter reducer

most common form is that of Banter merhant, a purveyor of banter

Banter is defined by what it tries and fails to be: spontaneous, funny, and tolerable.

Also known as "the wit of chavs".

laughter

used to describe an act which was done to have fun only.

Highly irritating word used by "people of a certain class" to describe the act of talking to someone who isn't a complete moron and can reciprocate said act. The word is one of about fifteen or so (for instance, "physically", "actually" and "grim") that are used excessively in conversations that do not call for their presence. To use the word "banter" to describe talking to someone, or, worse still, to use it proactively (see below) is a crime of speech and should garnish you a mother-fucker of a kick arse from all those around you who recognise you for the nob you are.

playfully insulting somebody, who will not take you seriously.