Uncle Andy has a wash (5)
I believe the answer is:
clean
'a wash' is the definition.
(I know that wash is a more specific form of clean)
'uncle andy has' is the wordplay.
'has' says the answer is hidden in the clue.
'CLEAN' can be found hidden inside 'uncle andy'.
(Other definitions for clean that I've seen before include "Unspoiled" , "Spotless; launder" , "Remove dirt or stain" , "Innocent" , "Without stain" .)