supplementary

US /ˌsʌp.ləˈmen.t̬ɚ.i/
UK /ˌsʌp.ləˈmen.t̬ɚ.i/
"supplementary" picture
1.

completing or enhancing something

:
•
The teacher provided supplementary materials for the students.
•
These notes are supplementary to the main lecture.
:
additionalextraancillarycomplementaryfurther