herbicide vs chemical

herbicide and chemical both are nouns.

Word	Noun	Adjective	Verb	Adverb
herbicide	Yes	No	No	No
chemical	Yes	Yes	No	No

As nouns, chemical is a hypernym of herbicide; that is, chemical is a word with a broader meaning than herbicide:

herbicide: a chemical agent that destroys plants or inhibits their growth
chemical: material produced by or used in a reaction involving changes in atoms or molecules

Other hypernyms of herbicide include chemical substance.

herbicide (noun)	chemical (noun)
a chemical agent that destroys plants or inhibits their growth	material produced by or used in a reaction involving changes in atoms or molecules

herbicide (adjective)	chemical (adjective)
	relating to or used in chemistry
	of or made from or using substances produced by or used in reactions involving atomic or molecular changes