Cleaner with mop has shot round (7)
I believe the answer is:
'cleaner' is the definition.
(shampoo cleans hair)
'mop has shot round' is the wordplay.
'shot' indicates an anagram.
'round' becomes 'o' (round can mean a round object).
'mophas' anagrammed gives 'shampo'.
'with' is the link.
(Other definitions for shampoo that I've seen before include "Soapy liquid for hair" , "Top cleaning product" , "cleansing liquid" , "Hair-cleaner" , "Hair or carpet cleaner" .)