josh vs chaff

josh is not a noun while chaff is a noun.

Word	Noun	Adjective	Verb	Adverb
josh	No	No	Yes	No
chaff	Yes	No	Yes	No

As verbs, josh and chaff are synonyms defined as:

Other synonyms of josh include banter, jolly, kid.

josh (noun)	chaff (noun)
	foil in thin strips; ejected into the air as a radar countermeasure
	material consisting of seed coverings and small pieces of stem or leaves that have been separated from the seeds

josh (verb)	chaff (verb)
be silly or tease one another	be silly or tease one another