reminder vs defender

reminder and defender both are nouns.

Word	Noun	Adjective	Verb	Adverb
reminder	Yes	No	No	No
defender	Yes	No	No	No

As nouns, defender is a hypernym of reminder; that is, defender is a word with a broader meaning than reminder:

Other hypernyms of reminder include guardian, protector, shielder.

reminder (noun)	defender (noun)
an experience that causes you to remember something	a person who cares for persons or property
a message that helps you remember something	a fighter who holds out against attack
someone who gives a warning so that a mistake can be avoided