SUNYATA

Sunyata in Buddhism means voidness or emptiness.  With sunyata the substantiality of the world is denied.  Everything is void.  Things are not what they seem to be, which is to say, in reality they are empty of the characteristics they are thought to have. 

For instance, in any act of everday experience where description is involved, the object described, the description, and the person doing the describing are all, in light of absolute truth, devoid of reality. 

They are not really existent in the way they are conceived to exist.  They are more phantasms than anything else.  The phantasms are real as phantasms, only their existence is relative.

In later years, after the Buddha, Nagarjuna further developed the idea of sunyata.  His view was that anything that is dependently originated, i.e. this is because that is first, is, again, void, empty. 

Put another way, anything that is transient, time bound, is sunyata.  This does not mean that such things are not experienced and, therefore, are non-existent, only that they are devoid of a permanent and eternal substance.

This supports both the Buddhist and the Vedantist notion of maya, where the world is seen as not really real, or real in only a limited sense.