sleepyhead vs doer

sleepyhead and doer both are nouns.

Word	Noun	Adjective	Verb	Adverb
sleepyhead	Yes	No	No	No
doer	Yes	No	No	No

As nouns, doer is a hypernym of sleepyhead; that is, doer is a word with a broader meaning than sleepyhead:

Other hypernyms of sleepyhead include actor, worker.

sleepyhead (noun)	doer (noun)
a sleepy person	a person who acts and gets things done