A few weeks ago, I contacted Leon Robinson from Kingston, Jamaica, who writes a blog called My thoughts...on stuff, and asked him if he would write something about Jamaican English as I have found his blog interesting and wanted to know his ideas about Jamaican English, which I hoped would add to the range of our view of English. We have contributors from many varieties of English, but little about the Caribbean. He agreed to do it and his thoughts can be read here.
Leon uses the term Jamaican Language where I used Jamaican English as he seems to see it as a language in its own right, which is a different perspective from the one I started with, but the differences between language and dialect or variation are far from clear- there is no acid test for what constitutes a language. Czechs and Slovaks seem to agree that they speak different languages, but there are greater similarities between their languages than between some of the dialects of Chinese. A language is defined by the speech community rather than outsiders.
Leon also pointed out that Jamaican language is replacing Cockney in London. A few months ago, I contacted someone from the East End of London to try to get more Cockney Rhyming Slang from them and they said the same thing, though in his case it was more of a lament for the decline of a truly fascinating dialect.
Among the examples of Jamaican language he gives, pickney for child, I know comes from the Portuguese pequenino, but I didn't know nyam for eat, which is, curiously, the same as in Khmer, which I am trying to learn at the moment.