Rubber duckie's spot (3)
I believe the answer is:
tub
'rubber duckie's spot' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for tub that I've seen before include "Open container, for liquid say" , "Wooden bath or slow boat" , "Large open vessel" , "subject of Jonson's tale" , "Slow boat; box of ice-cream" .)