post vs poster

post and poster both are nouns.

Word	Noun	Adjective	Verb	Adverb
post	Yes	No	Yes	No
poster	Yes	No	No	No

post (noun)	poster (noun)
a job in an organization	a horse kept at an inn or post house for use by mail carriers or for rent to travelers
the delivery and collection of letters and packages	a sign posted in a public place as an advertisement
an upright consisting of a piece of timber or metal fixed firmly in an upright position	someone who pastes up bills or placards on walls or billboards
military installation at which a body of troops is stationed
the system whereby messages are transmitted via the post office
a pole or stake set up to mark something (as the start or end of a race track)
A message on a social media website
any particular collection of letters or packages that is delivered
the position where someone (as a guard or sentry) stands or is assigned to stand

post (verb)	poster (verb)
display, as of records in sports games
mark or expose as infamous
cause to be directed or transmitted to another place
publicize with, or as if with, a poster
To post a message on a social media website
assign to a station
place so as to be noticed
mark with a stake
affix in a public place or for public notice
ride Western style and bob up and down in the saddle in rhythm with a horse's trotting gait
transfer (entries) from one account book to another
enter on a public list
assign to a post; put into a post