Lao-zi vs Laozi

Lao-zi and Laozi both are nouns.

Word	Noun	Adjective	Verb	Adverb
Lao-zi	Yes	No	No	No
Laozi	Yes	No	No	No

As nouns, Lao-zi and Laozi are synonyms defined as:

Lao-zi and Laozi: Chinese philosopher regarded as the founder of Taoism (6th century BC)

Other synonyms of Lao-zi include Lao-tse, Lao-tzu.

Lao-zi (noun)	Laozi (noun)
Chinese philosopher regarded as the founder of Taoism (6th century BC)	Chinese philosopher regarded as the founder of Taoism (6th century BC)