planchet vs disc

planchet and disc both are nouns.

Word	Noun	Adjective	Verb	Adverb
planchet	Yes	No	No	No
disc	Yes	No	No	No

As nouns, disc is a hypernym of planchet; that is, disc is a word with a broader meaning than planchet:

Other hypernyms of planchet include disk.

planchet (noun)	disc (noun)
a flat metal disk ready for stamping as a coin	a flat circular plate
	sound recording consisting of a disk with a continuous groove; used to reproduce music by rotating while a phonograph needle tracks in the groove
	(computer science) a memory device consisting of a flat disk covered with a magnetic coating on which information is stored
	something with a round shape resembling a flat circular plate