Where can I find a list of abbreviations used in tree diagrams of sentences?

Question

When I visited the EzTreeSee website at http://eztreesee.coli.uni-saarland.de/ and entered "Mary had a little lamb," I immediately encountered abbreviations that I had never seen before, to wit...

NNP VBD JJ NN

I've searched the net in vain for the meanings of these abbreviations. But that doesn't mean that there isn't a link.

So where can I find a list of abbreviations for the names of constituents identified in phrase-structure grammar trees?

Answer 1

We created eztreesee so that rank beginners can try out sentences without having to install parsers, models, etc. on their own computers. The backend runs entirely off the Stanford Parser. And therefore, what you see there are Penn Treebank tags.

The official documentation for PTB tags is this weird PostScript file; you might prefer this quickref.