supplementary
Definitions
Completing or enhancing something by providing additional information or material.
Added to something else in order to make it complete or to improve it.
Serving as an extra or additional component.
Examples
The teacher provided supplementary materials to help the students prepare for the final exam.
He took a supplementary course to improve his skills in graphic design.
The company offered a supplementary insurance plan to cover additional medical expenses.
Synonyms
additional auxiliary extra accessory complementary ancillary added