eavesdropper vs attender

eavesdropper and attender both are nouns.

Word	Noun	Adjective	Verb	Adverb
eavesdropper	Yes	No	No	No
attender	Yes	No	No	No

As nouns, attender is a hypernym of eavesdropper; that is, attender is a word with a broader meaning than eavesdropper:

Other hypernyms of eavesdropper include auditor, hearer, listener, snoop, snooper.

eavesdropper (noun)	attender (noun)
a secret listener to private conversations	someone who waits on or tends to or attends to the needs of another
	a person who is present and participates in a meeting
	someone who listens attentively