I. ˈ ̷ ̷ ˌ ̷ ̷ adjective
1. : being or able to be added on
add-on accessories
2. : of or relating to add-ons
3. : that can be added to
an add-on certificate of deposit
II. ¦ ̷ ̷ ¦ ̷ ̷ noun
( -s )
: something added on: as
a. : a sum or amount added on
b. : something (as an accessory or an added feature) that enhances the thing it is added to