add-on vs component

add-on and component both are nouns.

Word	Noun	Adjective	Verb	Adverb
add-on	Yes	No	No	No
component	Yes	No	No	No

As nouns, component is a hypernym of add-on; that is, component is a word with a broader meaning than add-on:

add-on: a component that is added to something to improve it
component: an artifact that is one of the individual parts of which a composite entity is made up; especially a part that can be separated from or attached to a system

Other hypernyms of add-on include constituent, element.

As nouns, component is a hypernym of add-on; that is, component is a word with a broader meaning than add-on:

add-on: a supplementary component that improves capability
component: an artifact that is one of the individual parts of which a composite entity is made up; especially a part that can be separated from or attached to a system

Other hypernyms of add-on include constituent, element.

add-on (noun)	component (noun)
a component that is added to something to improve it	an artifact that is one of the individual parts of which a composite entity is made up; especially a part that can be separated from or attached to a system
a supplementary component that improves capability	an abstract part of something
a software module that extends or enhances the capabilities of an existing application	something determined in relation to something that includes it