toy vs plaything

toy and plaything both are nouns.

Word	Noun	Adjective	Verb	Adverb
toy	Yes	No	Yes	No
plaything	Yes	No	No	No

As nouns, toy and plaything are synonyms defined as:

toy (noun)	plaything (noun)
any of several breeds of very small dogs kept purely as pets	an artifact designed to be played with
an artifact designed to be played with
a copy that reproduces a person or thing in greatly reduced size
a nonfunctional replica of something else (frequently used as a modifier)
a device regarded as providing amusement

toy (verb)	plaything (verb)
engage in an activity as if it were a game rather than take it seriously
manipulate manually or in one's mind or imagination
behave carelessly or indifferently