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Synonyms for Bottomless (same or very similar meaning)

WordNet sense 1 (having no limits in range or scope):
limitless, unlimited

WordNet sense 2 (having great spatial extension or penetration downward or inward from an outer surface or backward or laterally or outward from a center; sometimes used in combination):

WordNet sense 3 (not wearing clothing):

From the ODE community, based on WordNetadd/edit