barker vs bow-wow

barker and bow-wow both are nouns.

Word	Noun	Adjective	Verb	Adverb
barker	Yes	No	No	No
bow-wow	Yes	No	No	No

As nouns, barker and bow-wow are synonyms defined as:

Other synonyms of barker include doggie, doggy, pooch.

barker (noun)	bow-wow (noun)
informal terms for dogs	informal terms for dogs
someone who stands in front of a show (as at a carnival) and gives a loud colorful sales talk to potential customers	the bark of a dog