tai chi vs taichi

tai chi and taichi both are nouns.

Word	Noun	Adjective	Verb	Adverb
tai chi	Yes	No	No	No
taichi	Yes	No	No	No

As nouns, tai chi and taichi are synonyms defined as:

tai chi and taichi: a Chinese system of slow meditative physical exercise designed for relaxation and balance and health

Other synonyms of tai chi include t'ai chi, t'ai chi chuan, tai chi chuan, taichichuan.

tai chi (noun)	taichi (noun)
a Chinese system of slow meditative physical exercise designed for relaxation and balance and health	a Chinese system of slow meditative physical exercise designed for relaxation and balance and health