pinhead vs simple

pinhead and simple both are nouns.

Word	Noun	Adjective	Verb	Adverb
pinhead	Yes	No	No	No
simple	Yes	Yes	No	No

As nouns, simple is a hypernym of pinhead; that is, simple is a word with a broader meaning than pinhead:

Other hypernyms of pinhead include simpleton.

pinhead (noun)	simple (noun)
the head of a pin	a person lacking intelligence or common sense
an ignorant or foolish person	any herbaceous plant having medicinal properties

pinhead (adjective)	simple (adjective)
	(botany) of leaf shapes; of leaves having no divisions or subdivisions
	having few parts; not complex or complicated or involved
	easy and not involved or complicated
	exhibiting childlike simplicity and credulity
	unornamented
	lacking mental capacity and subtlety
	apart from anything else; without additions or modifications