posting vs show bill

posting and show bill both are nouns.

Word	Noun	Adjective	Verb	Adverb
posting	Yes	No	No	No
show bill	Yes	No	No	No

As nouns, show bill is a hyponym of posting; that is, show bill is a word with a more specific, narrower meaning than posting:

Other hyponyms of posting include show card, theatrical poster, flash card, flashcard.

posting (noun)	show bill (noun)
the transmission of a letter	a poster advertising a show or play
a sign posted in a public place as an advertisement
(bookkeeping) a listing on the company's records