bok choy vs pak choi

bok choy and pak choi both are nouns.

Word	Noun	Adjective	Verb	Adverb
bok choy	Yes	No	No	No
pak choi	Yes	No	No	No

As nouns, bok choy and pak choi are synonyms defined as:

bok choy and pak choi: Asiatic plant grown for its cluster of edible white stalks with dark green leaves

Other synonyms of bok choy include bok choi, Brassica rapa chinensis, Chinese white cabbage, pakchoi.

bok choy (noun)	pak choi (noun)
elongated head of dark green leaves on thick white stalks	Asiatic plant grown for its cluster of edible white stalks with dark green leaves
Asiatic plant grown for its cluster of edible white stalks with dark green leaves