Lexical Nets

Dear Everybody,

During last Friday's telco someone (I didn't pick out who) mentioned
something about lexical nets. I'm not sure about the definition or the use
of the term in this context, could someone please enlighten me as to what
it refers to (for example is it just a generic way of refering to wordnet,
verbnet, framenet, etc)?

Cheers,
Fahad