tummy vs potbelly

tummy and potbelly both are nouns.

Word	Noun	Adjective	Verb	Adverb
tummy	Yes	No	No	No
potbelly	Yes	No	No	No

As nouns, tummy and potbelly are synonyms defined as:

Other synonyms of tummy include bay window, corporation, pot.

tummy (noun)	potbelly (noun)
an enlarged and muscular saclike organ of the alimentary canal; the principal organ of digestion	a bulbous stove in which wood or coal is burned
slang for a paunch	slang for a paunch