Adds some information on the metamodel 👌

Which is the last thing missing from the glossary. So this closes #728

doc/Language/glossary.pod6

@@ -1164,6 +1164,8 @@ A character or group of blank characters, used to separate words. An example is
 =head1 6model
 X<|6model>
 
+6model is used in the L<MoarVM>, and provides primitives used to create an object system. It is described in L<this presentation by Jonathan Worthington|http://jnthn.net/papers/2013-yapceu-moarvm.pdf> and implemented L<here in MoarVM|https://github.com/MoarVM/MoarVM/tree/master/src/6model>.
+
 =end pod
 
 # vim: expandtab softtabstop=4 shiftwidth=4 ft=perl6