plait vs knife pleat

plait and knife pleat both are nouns.

Word	Noun	Adjective	Verb	Adverb
plait	Yes	No	Yes	No
knife pleat	Yes	No	No	No

As nouns, knife pleat is a hyponym of plait; that is, knife pleat is a word with a more specific, narrower meaning than plait:

plait: any of various types of fold formed by doubling fabric back upon itself and then pressing or stitching into shape
knife pleat: a single pleat turned in one direction

Other hyponyms of plait include box pleat, inverted pleat, kick pleat, tuck.

plait (noun)	knife pleat (noun)
any of various types of fold formed by doubling fabric back upon itself and then pressing or stitching into shape	a single pleat turned in one direction
a hairdo formed by braiding or twisting the hair

plait (verb)	knife pleat (verb)
weave into plaits
make by braiding or interlacing