Wallow (5)
I believe the answer is:
revel
'wallow' is the definition.
(I know that wallow is a more specific form of revel)
This is all the clue.
(Other definitions for revel that I've seen before include "Spree" , "Be festive, enjoy" , "Feast riotously" , "Carouse" , "Celebrate noisily" .)