blocker vs footballer

blocker and footballer both are nouns.

Word	Noun	Adjective	Verb	Adverb
blocker	Yes	No	No	No
footballer	Yes	No	No	No

As nouns, footballer is a hypernym of blocker; that is, footballer is a word with a broader meaning than blocker:

blocker: a football player whose responsibility is to block players attempting to stop an offensive play
footballer: an athlete who plays American football

Other hypernyms of blocker include football player.

blocker (noun)	footballer (noun)
a class of drugs that inhibit (block) some biological process	an athlete who plays American football
a football player whose responsibility is to block players attempting to stop an offensive play