(definitions from Dictionary.com)
16. Obsolete. the cant or jargon of
thieves, vagabonds, etc.
One of the challenges of
flash is get readers to identify with characters in a short time; also it’s how
to place readers within a different world when there’s no time to do it. Every
group has its own way of talking; every person has his/her own way of
expressing things. Use the particularities or “cant” of speech to get readers
immersed and identified.