1- an enjoyable and intellectually interesting conversation- not one about how hot it is today.
3- relax, stay in, do nothing...
4- Person who fits in well with a group of people who have a common interest and activity, normally getting very drunk and talking loudly in bars
5- a girl who acts, dresses and behaves in a boyish manner
6- say exactly what you think, directly, even if the other person might not like this
7- take the pee is like take the piss- it means to laugh at someone, tease them
8- it depends- they probably think it's positive, but many find zany characters wearisome. It means a bit crazy- people who are loud and unpredictable, for instance
9- a balanced, sensible person
10- I believe it involves dressing up in American clothes and dancing in a line
11- no idea- it could be 'trait', which is an individual characteristic