Drunken Len trips: that could be painful! (8)
I believe the answer is:
splinter
'could be painful' is the definition.
I can't tell whether this definition defines the answer.
'drunken len trips' is the wordplay.
'drunken' indicates anagramming the letters.
'len'+'trips'='lentrips'
'lentrips' with letters rearranged gives 'SPLINTER'.
'that' acts as a link.
Can you help me to learn more?
(Other definitions for splinter that I've seen before include "Small, sharp sliver" , "Long thin fragment" , "Small thin sharp bit of wood, glass or metal" , "Break into small pieces" , "Rent slip? (anag)" .)