lake bottom vs bottom

lake bottom and bottom both are nouns.

Word	Noun	Adjective	Verb	Adverb
lake bottom	Yes	No	No	No
bottom	Yes	Yes	Yes	No

As nouns, bottom is a hypernym of lake bottom; that is, bottom is a word with a broader meaning than lake bottom:

Other hypernyms of lake bottom include bed.

lake bottom (noun)	bottom (noun)
the bottom of a lake	a cargo ship
	the fleshy part of the human body that you sit on
	the lower side of anything
	the lowest part of anything
	a depression forming the ground under a body of water
	low-lying alluvial land near a river
	the second half of an inning; while the home team is at bat

lake bottom (adjective)	bottom (adjective)
	situated at the bottom or lowest position
	the lowest rank

lake bottom (verb)	bottom (verb)
	come to understand
	strike the ground, as with a ship's bottom
	provide with a bottom or a seat