pingpong table vs ping-pong table

pingpong table and ping-pong table both are nouns.

Word	Noun	Adjective	Verb	Adverb
pingpong table	Yes	No	No	No
ping-pong table	Yes	No	No	No

As nouns, pingpong table and ping-pong table are synonyms defined as:

pingpong table and ping-pong table: a table used for playing table tennis

Other synonyms of pingpong table include table-tennis table.

pingpong table (noun)	ping-pong table (noun)
a table used for playing table tennis	a table used for playing table tennis