Last of water filling pinkish kettle (6)
I believe the answer is:
corral
'kettle' is the definition.
(both can mean to confine people to an area)
'last of water filling pinkish' is the wordplay.
'last of' says to take the final letters.
'filling' is an insertion indicator.
'pinkish' becomes 'coral'.
The final letter of 'water' is 'r'.
'r' going into 'coral' is 'CORRAL'.
(Other definitions for corral that I've seen before include "Pen for livestock (US)" , "Pen for cattle - ring of waggons" , "Horse enclosure out West" , "Pen for cattle in the US" , "An enclosure for horses or cattle" .)