From the BigOmega page on GreenCheese:
So what is BigOmega? BigOmega is the limit to all of this. The number bigger than all numbers, ordinal, meta-ordinal or otherwise. The only number bigger than itself, violating all previous set-up rules. Of course, formally, there's no such thing. Its existence violates the OBR, and the meta-OBR, and all the others. Don't think too much about BigOmega. Cantor did, and he became mad.
Follow the link below for more on this. If you dare.
BigOmega Ω(n) is also the asymptotic lower bound of the complexity of an algorithm.
See BigOh, OrderNotation, ChiatinsOmega?
Pshaw. A trifle, this piddling BigOmega. You wouldn't want to be seen with something like that. Why, I've got a BiggerOmega? sitting in the lot out behind the dealership:
(actually a BuddhaBrot )