Synonyms: abysmal, abyssal, unfathomable
Definition: resembling an abyss in depth; so deep as to be unmeasurable
Usage: the abyssal depths of the ocean
Similar words: deep
Definition: 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
Usage: a deep well; a deep dive; deep water; a deep casserole; a deep gash; deep massage; deep pressure receptors in muscles; deep shelves; a deep closet; surrounded by a deep yard; hit the ball to deep center field; in deep space; waist-deep