Wet sticky earth (3)
I believe the answer is:
mud
'wet sticky earth' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for mud that I've seen before include "Alluvial deposit as in river bed" , "Sludge" , "-, -, Glorious - (Flanders and Swann)" , "slander" , "Offensive remarks" .)