hormone vs internal secretion

hormone and internal secretion both are nouns.

Word	Noun	Adjective	Verb	Adverb
hormone	Yes	No	No	No
internal secretion	Yes	No	No	No

As nouns, hormone and internal secretion are synonyms defined as:

hormone and internal secretion: the secretion of an endocrine gland that is transmitted by the blood to the tissue on which it has a specific effect

Other synonyms of hormone include endocrine.

hormone (noun)	internal secretion (noun)
the secretion of an endocrine gland that is transmitted by the blood to the tissue on which it has a specific effect	the secretion of an endocrine gland that is transmitted by the blood to the tissue on which it has a specific effect