Novel sort of piped disinfectant (5-3)
I believe the answer is:
sheep-dip
'disinfectant' is the definition.
'novel sort of piped' is the wordplay.
'novel' becomes 'she' (novel by H Rider Haggard).
'sort of' is an anagram indicator.
'piped' with letters rearranged gives 'epdip'.
'she'+'epdip'='SHEEP-DIP'
(Other definitions for sheep-dip that I've seen before include "Pesticide bath for proverbially silly animals" , "Farm animal's bath" , "Fleece disinfectant" , "Fleece cleaner" , "'Pesticide mixture for ovines (5,3)'" .)