growth regulator vs phytohormone

growth regulator and phytohormone both are nouns.

Word	Noun	Adjective	Verb	Adverb
growth regulator	Yes	No	No	No
phytohormone	Yes	No	No	No

As nouns, growth regulator and phytohormone are synonyms defined as:

growth regulator and phytohormone: (botany) a plant product that acts like a hormone

Other synonyms of growth regulator include plant hormone.

growth regulator (noun)	phytohormone (noun)
(botany) a plant product that acts like a hormone	(botany) a plant product that acts like a hormone