void

[1]	invalidate , annul , quash , avoid , nullify
[2]	invalidate , vitiate
[3]	evacuate , nullify , annul , empty , cancel , delete , disannul , declare/render null and void , invalidate , quash , vacate , discharge , abandon , disestablish , neutralize , disenact , set/put aside , rescind , reverse , abnegate , abrogate
[4]	evacuate , discharge , expel , emit , purge , clear , empty , drain , eject , pass , excrete , urinate , defecate

[1]	nothingness , nullity , nihility
[2]	vacancy , emptiness , vacuum
[3]	emptiness , vacantness , vacuum , blankness , nothingness
[4]	space , niche , slot , opening , place , vacancy , gap , emptiness

adj.

[1]	null and void , invalid , not (legally) binding , inoperative , unenforceable , ineffectual , futile , ineffective , vain , unavailing , idle , useless , pointless , bootless
[2]	empty , vacant , unoccupied , unused , unutilized , unfilled , blank , clear , deserted
[3]	void of , devoid of , without , lacking , destitute of
[4]	null