stitchery vs patchwork

stitchery and patchwork both are nouns.

Word	Noun	Adjective	Verb	Adverb
stitchery	Yes	No	No	No
patchwork	Yes	No	No	No

As nouns, patchwork is a hyponym of stitchery; that is, patchwork is a word with a more specific, narrower meaning than stitchery:

stitchery: needlework on which you are working with needle and thread
patchwork: sewing consisting of pieces of different materials sewn together in a pattern

Other hyponyms of stitchery include applique, binding, gather, gathering, darn, mend, patch, stitch.

stitchery (noun)	patchwork (noun)
needlework on which you are working with needle and thread	sewing consisting of pieces of different materials sewn together in a pattern
	a quilt made by sewing patches of different materials together
	a theory or argument made up of miscellaneous or incongruous ideas