Find grub, oddly in sink (3,2)
I believe the answer is:
dig up
'find' is the definition.
(thesaurus)
'grub oddly in sink' is the wordplay.
'oddly' means one should take alternating letters.
'in' indicates putting letters inside.
'sink' becomes 'dip' ('dip' can be a synonym of 'sink'**).
The alternate letters of 'grub' are 'gu'.
'gu' put within 'dip' is 'DIG UP'.
(Other definitions for dig up that I've seen before include "Unearth" , "Exhume" , "Disinter" , "Uncover (something hidden)" , "Excavate - discover" .)