Be holding it and get a nip from (4)
I believe the answer is:
bite
'get a nip from' is the definition.
I can't judge whether this definition defines the answer.
'be holding it' is the wordplay.
'holding' indicates putting letters inside.
'be' going around 'it' is 'BITE'.
'and' is the link.
Can you help me to learn more?
(Other definitions for bite that I've seen before include "Light meal" , "(Of fish) take the bait" , "power" , "Quick snack" , "Injury from teeth" .)