Go quickly back again (3)
I believe the answer is:
pop
'go' is the definition.
(popping is a kind of going)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for pop that I've seen before include "Explosive sound; drink" , "Youthful music for dad?" , "Music with mass appeal" , "US fizzy drink and type of music" , "Soft drink - father - music - light explosion" .)