Meaning : Fill something that had previously been emptied.
Example :
Refill my glass, please.
Synonyms : fill again, replenish
Meaning : A prescription drug that is provided again.
Example :
He got a refill of his prescription.
The prescription specified only one refill.
Meaning : A commercial product that refills a container with its appropriate contents.
Example :
He got a refill for his ball-point pen.
He got a refill for his notebook.