attender vs helper

attender and helper both are nouns.

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

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

attender: someone who waits on or tends to or attends to the needs of another
helper: a person who contributes to the fulfillment of a need or furtherance of an effort or purpose

Other hypernyms of attender include assistant, help, supporter.

attender (noun)	helper (noun)
someone who waits on or tends to or attends to the needs of another	a person who helps people or institutions (especially with financial help)
a person who is present and participates in a meeting	a person who contributes to the fulfillment of a need or furtherance of an effort or purpose
someone who listens attentively