crammer vs schoolbook

crammer and schoolbook both are nouns.

Word	Noun	Adjective	Verb	Adverb
crammer	Yes	No	No	No
schoolbook	Yes	No	No	No

As nouns, schoolbook is a hypernym of crammer; that is, schoolbook is a word with a broader meaning than crammer:

Other hypernyms of crammer include school text, text, text edition, textbook.

crammer (noun)	schoolbook (noun)
a textbook designed for cramming	a book prepared for use in schools or colleges
a special school where students are crammed
a student who crams
a teacher who is paid to cram students for examinations