adjective.Impervious to limitation, without limit.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
adjective.
without limits in extent or size or quantity
Word Usage
"Perhaps the idea of illimitable extent is better conveyed by the lithographic sketch, No. 8, in which the level, not being interrupted by the intersection of a mountain ridge, as in the former, vanishes in distance."