supplemental; not inherent or original
That serves as an addition
The situation where a student who holds a qualification equivalent to part of a degree course is then accepted onto a degree course at an intermediate point, without having to start it from the beginning.
Additional credit purchased for a mobile phone.
An addition.
An additional premium paid over the initial premium in order to increase benefit values.
A serving of drink used to top up an existing glass.
A dose of epidural anesthetic added to previously injected spinal anesthetic in combined spinal-epidural anesthesia