Small turtle avoiding soft ground (7)
I believe the answer is:
terrain
'ground' is the definition.
(terrain is land or ground)
'small turtle avoiding soft' is the wordplay.
'small turtle' becomes 'terrapin' (I've seen this before).
'avoiding' indicates named letters should be taken away.
'soft' becomes 'p' (musical abbreviation for piano, 'soft').
'terrapin' with 'p' taken away is 'TERRAIN'.
(Other definitions for terrain that I've seen before include "Stretch of land with respect to its character" , "Land (as base for action)" , "Area of ground with a particular characteristic" , "Physical features of a tract of land" , "Topography" .)