top-up

Energy will be generated from solar panels, water will be recycled and extracted from soil and the astronauts will grow their own food - they will also have an emergency ration and regular top-ups as new explorers join every two years.

I added a $20 top-up on my cellphone's data plan.

The reinforcement of anesthesia by an epidural “top-up” in combined spinal-epidural anesthesia may be explained by a dual mechanism: a volume effect compressing the dural sac and a local anesthetic effect.