I saw this on corpora-list, and thought they could come in handy for us.
I don't understand what you exactly mean by basic vocabulary used for defining words but if you mean roots from which Arabic words can be generated, here are two dictionaries. In our team we have two Arabic dictionaries available in LMF format
Contemporary Arabic dictionary with 32300 lexical entries generated from 5778 roots
Al wassit" Arabic dictionary with 61101 lexical entries generated from 6900 roots
I saw this on
corpora-list
, and thought they could come in handy for us.