fatty tissue vs belly

fatty tissue and belly both are nouns.

Word	Noun	Adjective	Verb	Adverb
fatty tissue	Yes	No	No	No
belly	Yes	No	Yes	No

As nouns, belly is a hyponym of fatty tissue; that is, belly is a word with a more specific, narrower meaning than fatty tissue:

fatty tissue: a kind of body tissue containing stored fat that serves as a source of energy; it also cushions and insulates vital organs
belly: a protruding abdomen

Other hyponyms of fatty tissue include flab, atheroma, cellulite, puppy fat, mons, mons pubis, mons veneris, paunch, love handle, spare tire.

fatty tissue (noun)	belly (noun)
a kind of body tissue containing stored fat that serves as a source of energy; it also cushions and insulates vital organs	the underpart of the body of certain vertebrates such as snakes or fish
	the region of the body of a vertebrate between the thorax and the pelvis
	a protruding abdomen
	the hollow inside of something
	a part that bulges deeply

fatty tissue (verb)	belly (verb)
	swell out or bulge out