Rower back from Henley cleaning room (8)
I believe the answer is:
scullery
'cleaning room' is the definition.
'scullery' can be an answer for 'room' (scullery is a kind of room). I'm not certain of the 'cleaning' bit.
'rower back from henley' is the wordplay.
'rower' becomes 'sculler' (sculler is a kind of rower).
'back from' says to take the final letters (the letter at the back of the word).
The final letter of 'henley' is 'y'.
'sculler'+'y'='SCULLERY'
Can you help me to learn more?
(Other definitions for scullery that I've seen before include "Room for non-cooking kitchen work" , "Small room next to the kitchen" , "Where dishwasher went" , "Room for rough kitchen work" , "part of kitchen" .)