Tool drier, last of water absorbed (6)
I believe the answer is:
trowel
'tool' is the definition.
(trowel is a kind of tool)
'drier last of water absorbed' is the wordplay.
'drier' becomes 'towel' (I've seen this before).
'last of water' becomes 'r' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'absorbed' is an insertion indicator.
'towel' going around 'r' is 'TROWEL'.
Can you help me to learn more?
(Other definitions for trowel that I've seen before include "Small garden hand-tool" , "Scoop-shaped tool with short handle" , "Short-handled gardening tool" , "Mortar-spreading tool" , "Hand tool for plasterers or gardeners" .)