It has its sandy side (3)
I believe the answer is:
sea
'sandy side' is the definition.
The answer and definition can be both natural objects as well as being singular nouns.
Maybe there's an association between them I don't understand?
'it has its' is the wordplay.
'it' becomes 'sa' (SA can mean sex appeal, as in 'it').
'has' indicates putting letters inside.
'its' becomes 'e' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'sa' placed around 'e' is 'SEA'.
Can you help me to learn more?
(Other definitions for sea that I've seen before include "Large body of salt water" , "Body of saltwater" , "eg Galilee" , "eg Dead, Red" , "Cod's home?" .)